Has anyone found an aftermarket thumb wheel switch that works on a cat 226b skid steer it's on the right joystick . Mine has gone completely missing and the replacement is cost too much. Is there any alternative switch that can work in its place to get the auxiliary working again. Even the the data sheet for the switch would be useful.
I've tried that switch is used in alot of applications last one I replaced the handle was 500 bucks or so
The Roller Switch is not available separately and there are no details of it kicking around anywhere that I have come across. This question has been asked a number of times and no information such as specfications, etc, has ever surfaced. The only option is to replace the complete handle assembly.
I am in the process of fixing my thumbwheel switch on my 226b. i found the switch and ordered it, will be arriving in a couple days. as soon as i get it installed ill let everyone know the results. in the mean time check out the attached file hope this helps someone. the mfg of the switch is otto
Welcome to HEF quicksilvr ! I hope it works for you. If it does, your information will sure help other members in the same predicament.
Not trying to be a wet blanket, but let me point out one thing here............... According to the data sheet the switches in the link in quicksilvr's post above appeat to give a variable voltage output dependent on the movement of the thumbwheel. The OEM thumbwheel is a PWM-type sensor that outputs a variable square wave, the duty cycle of which is proportional to the movement of the roller away from centre. It is that duty cycle signal the ECM of the machine is looking for. The voltage of the output does not vary AFAIK. EDIT: A bit of research has led me to the conclusion that the output voltage of the thumbwheel signal can vary a little between certain fixed upper and lower limits. Above or below these limits will generate Diagnostic Codes for either "Voltage High" or "Voltage Low" for the thumbwheel sensor, but to reiterate the signal that the ECM is looking for is a duty cycle signal (see below) and not a variable output voltage from the thumbwheel. Specifically the thumbwheel signal will be approximately 50% duty cycle in the centre position, around 10% duty cycle when fully rotated in one direction away from centre, and around 90% duty cycle when fully rotated in the other direction.
Now these with an optional PWM output might work ... https://www.megatron.de/en/products/thumb-joysticks/thumb-joystick-series-try13m.html?dv_t3_referrer=https://www.google.com/
when my thumbwheel switch stopped working, i disassembled it to find the magnet had rotted away and was nothing more than a clump of material. so as a temporary fix, i removed the clump of useless material and used jb weld to attach a small piece of magnet that i recycled from a laptop hard drive. it brought back partial functionality, my tiller attachment will spin forward but just not in reverse.
with a dmm attached to the temporarily fixed thumbwheel switch, i had 5v at center 5.72v in one direction and 3.93v in the opposite direction. and yes that was at full travel. the voltage readings were stable and not fluctuating or pulsing
The link to the switch that you originally posted might just work in that case. I was under the impression that they were all PWM-type, but maybe the very early models were Hall Effect. Hopefully someone else can offer an opinion.
ohh the switch is deinately hall effect without a doubt. lol
I have to apologize. I misread the model as a D Series. Having done a bit of research it appears as though the later C & D-Series machines have a thumb roller sensor that is a PWM type. On the electrical schematic for those machine the thumbwheel input is marked "FREQ/PWM Input". For the B models the same input to the ECM is marked "Proportional Signal" i.e. Hall Effect. Either way it appears that either the link you supplied or the other one that I found ought to be a solution to whichever type of control handle switch is installed on a particular machine.
its all good..... im excited to get this switch. if im right and this works, it will help out so many people with the same issue
Absolutely. I'm thinking further ahead that if what you're doing with a Hall Effect thumbwheel works as intended, then it would only be a small step to replacing a PWM thumbwheel in a later model machine. All it would need is a mini thumbwheel with the appropriate type of internals. Anything has to be better than a $500 handle...........
indeed which is where the link you posted will come im handy.
Do you have an electrical schematic for your machine.? I assume it's MJH S/No prefix. If it would help I can send you a copy. Need to know if your S/N is below 10575, or above 12175, or in between the two numbers.
no unfortunately i do not. yes thats the S/N prefix. that would be great if you could
There are 3 schematics - S/N under 10575, between 10575 & 12175, or above 12175. Which category does your machine fall into.?
gimmie a min ill go look
mjh03996
For some reason it seems that your profile will not accept PMs. Try PM'ing me and you can have the schematic by return.
ok i fixed it
ok well heres the latest update. i got the switch (htwm-1a11a22) from mouser.com. and its not working at all. i connected a dmm to the switch ground and output wires while it was connected to the skidsteer and engine running i have 8v and when i roll the switch to full travel in either direction, i see no change in voltage at all. HOWEVER, i did manage to fix the old switch by replacing the disintegrated magnet with a different magnet. it works in forward and reverse. YAY! it took me a few hours with a dremel tool and a neodydmium, or however its spelled, magnet. i basically had to trim the magnet into 2 tiny square blocks and super glued them in place making sure that both magnets that were facing downward toward the sensor were the same polarity.
That’s disappointing. I wonder if the manufacturer would supply some details about how it’s supposed to work such as input voltage requirements, etc.
yea i hope they do something bcuz that switch cost $100 delivered to my door lol
here is what i have as far as specs go for that switch...
Well there's something straight off. Required supply voltage is in the range of 4.5-5.5v DC with 5v being the target figure. In a Cat SSL the switch is being supplied with a stabilized 8v DC supply produced internally within the ECM. Do you have any way of supplying it with 5v DC and see how it behaves then.? Also try connecting a DMM between the switch "output signal" wire and machine frame ground instead of the stabliized power ground that you connected it to before. See if that makes any difference. Not sure about the voltage output options TBH. Can you measure the voltage from your repaired switch at 3 positions (centre, full FWD, & full REV) and post up the results.
ya know i was thinking the same thing. ill see what i can do as far as supplying it with 5v. as for the ground, i tried ground at the switch and the machine ground and the reading was the same. i will take measurements of the repaired switch and post them here in a lil bit
ok well i supplied the NEW switch with 5.08vdc, and the readings i got at center: 2.89vdc, full forward: 4.52vdc and full reverse: .508vdc
So that would seem to indicate that it doesn’t like being supplied with 8v....
yea ur right about that. i guess i didnt do my homework as well as i thought i had. interestingly enough, on the old switch being modified, with the supply voltage obviously being 8vdc the voltage on the output wire was 5vdc@ center, 6vdc@ full forward and 4vdc@ full reverse. so the internals of the switch must have a voltage regulator? but none the less, i have no choice but to eat the cost of this switch and chalk it up as a lesson learned.
so i guess the trick is going to be locating a similar switch that will function with 8vdc supply.
Or contact the switch manufacturer and inform them that you have an application where, due to machine on-board limitations, the supply to the switch MUST be 8v DC rather than 5v, and ask them if they can suggest a solution. You could also mention that it is a piece of mobile equipment that you are talking about.
im on their site now looking to see if they have any listed. ill contact them and ask. im about 99.9% certain its made by otto, because the trigger switch on that same joystick says otto on it. why this switch doesnt have any markings is beyond me
Has anyone had success with any switches thus far?
i had luck repairing mine, i just dug out the old magnet and replaced it with a rare earth magnet that was cut into 2 tiny pieces
Mine is completely missing unfortunately.
the entire switch? damn that sucks. i do know that the maker of the switch is otto, at least mine was. i gave up looking after i fixed my switch. u can try contacting them. the switch needs to be designed to operate with an 8vdc power source. all the switches on their website are designed for 5vdc power source, so they wont work. i already tried one of them and ended up wasting around $100. lol
Do you have any idea on what is the output voltage for the switch when using 8vdc?
yes, mine had 5.72v at center, 3.93v forward full travel and 4.94v reverse full travel. those were the initial readings prior to repairing the switch. i did not take any measurements after the repair tho.
Has anyone found a thumb roller switch that will work with 8v? Thanks Wayne
the only one i found was for 5v. i ended up repairing mine by replacing the magnet
Thanks, I will take mine apart and try to repair it. I can't hardly believe that a replacement switch is not available.
ibelieve they were specially made just for caterpillar and not available on open market
You are correct. They had to be specially made because of the ECM producing stabilized 8v power which is a standard supply voltage for Cat PWM sensors.
well not all hope is lost, it is possible to repair them. if anyone is willing to ship their thumbswitch to me, ill gladly fix it for them.
I will be going back to the machine in a couple weeks and take it out. I'll take it out and look it over. l may send it to you if I can't fix it. Thanks Wayne
okie dokie let me know
Ok, Thanks, Wayne
Hey quicksilver I’m trying to get sum info on thumb roller for my cat skidsteer can u please help me?
Hey quicksilver I’m trying to get sum info on thumb roller for my cat skidsteer can u please help me?
Any leads on thumb wheel?
Do I just cut the wires or is there some other to get it out? Thanks,Wayne
there is a connector where it plugs into the main harness near the floorboard
I have the thumbswitch out and would like to send it to you. please email me at [email protected] with instructions.
ok i emailed you my email is [email protected]
For those who are wanting to send me their thumbwheel switches, i want to make it very clear that i am by no means an expert at any of this nor do i guarantee that ill be able to fix your switch. I WILL try my best to fix them. Im saying this now bcuz i dont want to mislead anyone or have anyone get their hopes up in the event that im unsuccessful at fixing it.
257B2 My thumb switch is a little stiff, is there a lubricant that can smooth out the action? If there are any updates on an available replacement switch I’d like to keep updated.
Try some type of silicone spray. Failing that you may have to (very carefully if the switch is working at the moment) disassemble the switch and clean it inside.
i would just leave it, as long as it works. if you spray any lube in there, you risk dislodging whats left of your magnet
If the magnet inside the switch has not yet deteriorated beyond the point of no return would it be worthwhile to open it up now and try to salvage it before it completely disintegrates.?
there wouldnt be any way to salvage any of it. id just leave it be until it stops working
ive had sum luck with replacing the magnet on these. if you want to send me the switch, i can repair it for you. if interested, pm me
Hey all - I started with this thread down a journey to solving the issue without buying a whole joystick. I ended up 3D printing a new roller switch. Here are the 3D models that you can 3D print on your own. I used a small bar magnet out of an iPad cover for the hall effect sensor to 'sense'. You may need to tweak the design to fit whatever magnet you use. Seems to work best with a small bar magnet with N and S at each of the long ends (as opposed to N S being on opposite sides of the flats). https://www.tinkercad.com/things/2L6WHEd56j5 My springs were as rusted as the magnet was. I replaced the springs with a spring out of a pen - one of the click style. I had to try a few pens before I found one that was just right - I cut the pen spring in half and used each half on each end of the roller. The 3D print has a couple of spikes sticking out to center the springs and then I used heavy duty hot glue to attach the springs to the roller. Let me know if anyone else is successful with this - I hope it's helpful to someone else who doesn't want to spend $850 bucks on a fricking joystick.
sounds awesome. good thinking.
@Ryan Bunce or @quiksilvr do you guys have some pics you could share of your repairs? I got mine apart and found that part of the magnet was melted/rusty on one end. Filed it down since it was contacting the potting on the switch itself. Now it's working intermittently which is kind of annoying and was looking at a whole new replacement switch from Otto. Big thanks to @Nige for pointing me here, it saved me buying a switch that I couldn't use.
i will look for the pics i took, i just gotta remember what i did with them lol
Here's a pic of the roller before with the rotted magnet and a pic of the 3D printed copy that I made and combined with a bar magnet.
Thanks guys. Mine was nowhere near as bad as yours @Ryan Bunce , just the on end of my magnet was rotten. I'm curious about magnet placement, more specifically which way are the north/south poles of the magnet orientated?
I don't remember off the top of my head the Pole orientation but if you give me some time I will go out to my machine and take my switch off and get some pictures of it and double check the polarity of the magnets for you
That'd be awesome if it's no big deal. If not, mine is still mostly in-tact so I can figure it out myself.
the first pic shows the way i tested mine without disassembling the switch itself using a small magnet i had as an extra. with switch plugged into the machine, take a magnet and run it in the direction noted in pic. you should get some type of response from the machin. if nothing happens, then ur *** and gotta buy a new joystick
the 2nd pic shows the way i tested mine without disassembling the switch itself using a small magnet i had as an extra. with switch plugged into the machine, take a magnet and run it in the direction noted in pic. you should get some type of response from the machin. if nothing happens, then ur *** and gotta buy a new joystick
as for magnet orientation, u want similar poles facing each other.
Thanks! I'll find some new magnets and take mine apart to test the switch. I'll report back with my findings. I've also contacted Otto to see if they have 8v switches available as another repair option.
For my 'fix' it didn't seem to matter which orientation I put the magnet. As long as either of the +/- ends of the bar magnet would sweep radially through the hall sensor, it worked. I presume that the original round/doughnut magnet has it's poles oriented on its hemispheres rather than its flat sides. These are called 'diametrically magnetized'. There are some places you can get diametric, ring magnets. Might be worth a try. See here: N42 Neodymium Diametrically Magnetised Ring Magnet - 1/4 in. O.D x 1/8 in. I.D x 1/32 in. thick 6mm outer diameter x 3mm inner diameter x 1mm thick.0.24 in. outer diameter x 0.12 in. inner diameter x 0.04 in. thick.+/-0.1mm (0.004 in.) tolerance.Each magnet's north and south pole are on opposite curved sides.Excellent resistance to demagnetisation.Coated with three layers of nickel, copper... www.first4magnets.com
thanx for that insight, im no expert in magnets so its nice to have someone here who knows more about them than i do.
I finally got a break in the weather and got to diagnose a bit further. The auxiliary control has been intermittent with no real rhyme or reason to it's functionality. I took things apart again today and tested out the switch itself using the diagram posted earlier. There doesn't appear to be any issues with voltage output from the switch and I'm leaning towards a wiring issue in the joystick itself. I'm thinking this because I was able to get intermittent function while moving the harness. I took some of the loom off but didn't see anything obvious. Now I've lost all functionality though and I'm wondering if this is the ECU protecting itself? I think my next steps are removing the joystick itself from the machine and testing the wiring on the bench. Thoughts?
did you check the connector at the end of the joystick harness? its located under the joystick near the floorplate. u have to take the grey plastic cover off that is underneath the joystick
after having fixed a few of these for people, im beginning to notice that on some of the thumbwheel switches, when the magnet goes bad, its not too long after, that the sensor inside the switch ends up going bad. and thats the point of no return for the switch.
Not yet, but that's where I was heading. I'm just trying to remember if I have to lift the cab to get that vent/trim out.
no u dont have to, i used a torx bit with a pair of vise grips to turn it and u can squeeze between the cab and the cover not much room but it is do-able
My switch has a fair amount of "wear" in the potting from the blown out magnet rubbing against it, so I wouldn't doubt it could be going bad too. We have 3 x 216B in the scrap pile at work that I should try a new joystick from. I'm not sure if those would even have auxiliary switches on them though.
if you are referring to the concave indentation on the sensor portion, that is from the factory.
That's the one, that's good to know! I thought mine was worn down from the magnet. Hopefully the weather holds out after work sometime this week so I can take things apart a little further.
there is a way to check the sensor portion of the thumbwheel switch, if you have a spare magnet laying around. you can run a magnet along the bottomside of the switch. with the switch connected to the machine and the machine running. if the sensor is still good, then you should get some kind of response from the machine.
It's been awhile since I have been on here. Ohio weather bites.Thank you quiksilvr for trying to fix my thumb roller switch. It still didn't work so I ended up getting a new joystick and in the initial test that seems to have fixed the problem. Thanks to everyone for their advice and suggestions. Wayne
By the way some of Cat engineering is kinda suspect. lol
I got some time to work on mine today. I pulled the joystick and harness out of the machine and tested it on the bench. I ended up finding no continuity in the output circuit (yellow wire) which lead me to finding a break in it. I repaired the wire with what I had on hand and put everything back together. It's now working consistently in both directions which is awesome. However, the positive flow output is very weak/slow while the return is overly quick. I'm not sure if there's a calibration I have to do on the auxiliary circuit?
I pulled the negative terminal in hopes of resetting any sort of calibration on the machine, no luck. I looked into what the purple wire does and it looks like that might just be for a factory calibration, it doesn't actually connect to anything on the machine side of the harness. I'm debating on removing everything again, and redoing my splices with crimps instead of solder. Maybe I have some excess resistance from the repair? I guess the other issue could be the one magnet on my switch being in worst shape than the other, but it's very minute.
A soldered connection is way better then a crimped one. That said, you probably couldn't measure the difference between a soldered connection and a properly crimped connection. The soldered connection is less likely to fail down the road.
Do you have an electrical schematic.? If you don’t and you want one pls supply a serial number.
Thanks for the offer! I still have the one you got me from the drive motor/parking brake thread!
So what is the reference number of the purple wire of which you speak.?
I'm not sure what the reference number is, but it's the Violet (VI) wire coming off ROLLER - PROPORTIONAL A1/A2. It doesn't have a pin on the machine side of the harness so I figured it doesn't have a use while in the machine.
That must be either the complete handle assembly is designed to be externally calibrated in another type of application, or just the thumbwheel switch (from an outside supplier) is designed for external calibration in another application. No calibration required in your application, it either works or it doesn't
Is it possible that Cat ET needs to be used when replacing the switch to set some calibration in it? I'm still planning on re-doing my repair, I ended up putting 3 repair joints on the yellow wire and would like to bring that down to one.
No. There is no calibration for the thumbwheel switch. If it has been correctly manufactured it will put out a voltage output that varies from around 5.7v in the centre, and increases/decreases by up to approx 0.8v depending on whether you roll the switch forward or back.
I was blessed with 18 inches of snow yesterday so got a chance to use the machine again. It looks like the issue might have corrected itself, and/or the switch wasnt really the issue. Everything works like it should now, both open and close functions on my bucket seem balanced now. One of the hydraulic hoses on the bucket got damaged (pinched) from bad routing some time ago, I'm thinking that was really my issue after all.
Thinking about my post #99 above and trying to explain it better. It's not the measured output voltage on the "roller signal" connection from the switch that determines the actions of the ECM. Whatever is the voltage with the switch in the centre position becomes the "reference voltage", and it doesn't really matter what that voltage is but the ECM notes it. From that point the change of output voltage resulting from the thumbwheel switch being rolled backwards or forwards is what triggers the ECM into action to do whatever action it's programmed to do based on the change of input voltage from the reference value. So getting hung up the value of the output voltage from the switch can become somewhat of a distraction.
I have same issue with same switch on telehandler. (it has 2) Swapped magnets and worked for a couple hours and failed again. After sitting works fine. Can it fail internally after warming up? Is there an otto replacement. Was looking at buying one to try but not sure why it didnt work
Otto won't sell the cat specific ones when I tried. My issue ended up being some broken wires coupled with a "swollen" magnet.
The Cat thumbwheel switch requires a dedicated 8v DC supply. Otto do not sell a switch of the specification, at least not commercially, although I have long suspected that they manufacture the switches for Cat.
I dont know if this helps, but I’m working on a 308E2 that has a problem with this roller switch. I finally decided to take a crack at it again today. Problem: has thumb attachment, rolling forward, opens the claw, rolling down, nothing happens. No change in engine speed, no pressure in the hydraulic tubes. Went from working to non-working same day, after lunch break, no changes to the machine, no apparent codes. Testing: measured signal on both left and right stick rollers. Center is 4v, full forward is 1.9V, full down 6.23V. Left roller functions up and down. My thoughts: will the hz function on my dmm serve me better here than the voltage setting? According to specs, output is 500hz plus/minus 80. Thats 460-540hz range. The dmm displays the RMS, so the voltage being read may not be proportional to the duty cycle. Speaking proportionally, 8*.2= 1.6v, meaning Im off by .3v, same with the other side. I took another magnet and ran it and played with it, but could not get it to respond in the “down” direction. The switch was surprisingly clean too. Beyond a possible open connection, or faulty ECU, what else am I not considering?
Crap. I think I posted that all wrong/wrong place
i think you'll be ok with posting it here for now.... as for the thumbwheel switch, have u tried removing the switch from the joystick and opening it up to have a visual of the magnet inside?
the reason i ask is that its possible only half of the magnet is intact.... if u can open up the switch and verify, that would help
I did. Was very clean, wires going to are great shape, no rust on the springs. Tried to get it to function by placing the rollers magnet on back-side of the sensor with no reaction, to that or a bigger magnet I could find. Tried to cleverly reverse the magnet, approach the sensor from the bottom, then pass through to the top, could only activate the one side. Thank you btw, not often do you get a response from someone quickly
No. If the switch is the same as the Skid Steer one it is a Hall Effect switch and the output variations that are used as inputs to the ECM are seen as a variation in voltage, nothing to do with frequency. Are you saying that the output voltage variation of the LH & RH switches are approximately the same but one switch works (as in the function it controls does what you want it to do) and yet the other one doesn't.?
I’ll confirm this tomorrow early morning, but testing both LH/RH both showed very similar readings. I wrote down the values on the problem side, but sweating it out, I forgot to write down the LH. perhaps Im getting them [hall effect] confused. This is a newer 308E2… Im green to cat, but advanced in engineering. Got three cats to get back to purring - skid steer, the 308, and the backhoe. I think I’m gonna be on here a bit.
A Serial Number might help. I can look at the switch on the electrical schematic. While I think about it, when you’re measuring the output of the switch and the input to the ECM, do it by back-probing with the wiring connected. That’s the only way to get accurate results.
I seem to remember the voltages being the same on both sides. If the LH shows closer to 1.6v/4v/6.4v v.s. RH 1.9v/4v/6.23v Then we can probably lean towards a bad switch. Interestingly, 1.9 is further off than 6.23v. Thank you again, I’ll get you that info tomorrow morning. Moving boulders by yelling at them isnt working. Would be rewarding to figure this out
Those voltage numbers seem pretty "normal" from what I remember, although every switch can be a little bit different. AFAIK the ECM responds to a change in voltage from the switch not the actual input voltage. Around 4.0v in the centre, and about 2.4-2.5v above/below that when the thumbwheel is rolled front and rear.
Hit it this morning again, both sides read about the same, the variations being proportional to the input signal so, running/stopped the voltages are different.m- this is probably why they went with PWM. Both sides measured ~4v @ center, ~1.88v up, 6.22v down. So, the issue doesnt seem to be the switch (unless its PWM signal is funky - which I dont have the means to test). Im going to trace and test at the ECU.
The output of this particular switch is not PWM, it's a varying voltage as a result of the Hall Effect. Testing it using the DC range of your multimeter, provided that you are backprobing the pins with the switch still connected to the machine harness, is fine. If it was a PWM switch (as fitted to later models) the output voltage from the switch would remain constant but the width of the output pulse would change in response to switch movement. That's where you would need a multimeter capable of measuring Duty Cycle - which is not the same as frequency.
Thats right I was supposed to supply serial num. just got in from taking the horses for a ride. Burnt. Will get after lunch and celebrations. Its 2015/2016 308e2 is what i got for you for now
Could it be a a solenoid that actuates the hydraulic valve that could be an issue? Meaning, whatever the thumb wheel is telling the ECM the ECM is telling a valve or solenoid somewhere to open and close.
FYI…All. My thumb wheel has been working intermittently ……took it part today and found three of the wires broken inside the sheath. The wire sheaths were totally intact.
How did that thumb wheel switc you ordered work out? Was it a plug and play or were their complications? I’ve got a 257B2 and its thumb wheel switch is becoming hard to rotate and sticks.
It wouldn’t work. It’s somewhere in the thread. Start from Post #23 on Page 2. The Cat switch requires an 8v supply and unfortunately the only switches on the open market all specify a 5v supply. Supplied with 5v they work great, supplied with 8v they don't.
Hi, The right joystick thumb switch died on our 2007 257B2 this past month. I use a grapple attachment a lot. I had CAT mobile service in today for a look. For what it might be worth, his determination is that the ECM (part # 2160658) under the floor board is not working correctly. He said, "There is no output from pin 40 and pin 42 which is for A1 solenoid and no ouput for pin 58 and pin 42 which is A2 solenoid. This is directly from the ECM. The inputs are working as they can read using the laptop but nothing comes out of the ECM as 12 volts on pin 1 and 3." So now I'm looking at whether or not to get a reman ECM or sell the machine as is.
Did this switch work?
No. See my post #122 just above.
I have the same issue with my switch 259b3 cat. I am wondering about contacting the manufacture you bought your switch from and having 100ish of them made with the right 8v and then perhaps selling them on an eBay store. ♂️ You guys are much more knowledgeable than me. Great feed. Thanks to all for the knowledge. Glad there are still guys out there fixing there equipment like me.
I wonder if they would sell 100 of them if i didn’t mention caterpillar. It would be worth reselling them on eBay to help you guys out. I need one.
Good idea.
With the right item description, I think you'd have an easy time selling them. Hopefully the manufacturer will play ball.
For something that size you might have to be talking 10,000 pieces rather than 100 to make it worth their while.
You’re probably right and seem very knowledgeable. I have a cat 259b 2012 and need to install a 14 pin wiring harness on the machine I believe it was taken off previously. I can not find any information or videos of guys installing them. What’s the best place to get a wiring diagram? I ordered the conversion from skid steer genius to go to 8 pin but need to solve this issue first. New member so not sure if i should create a thread about this? Thanks.
You want an OEM electrical schematic for the machine, correct.? Serial Number identifies the appropriate schematic.
Yyz03941 2012 cat. I entered my serial number on cats website, and they provided minimal information. I will keep looking online today with my specific serial number. Thank you.
I'll send you the electrical schematic. Keep an eye on your messages.
Hey sir I sent you an email. I messed w new cut magnets and when it was oversized I got it to work… but after dremmel time and getting it to roll… I have nothing again. What magnets are you using? I got some rare earth bars from Amazon but as soon as they get small the polarity is off and no strength
How do you get the plastic cover off? Seems a couple torx bolts on the back side? Guessing patience and a t20 wrench
Hello all, Thank you for all of your input. I just bought a 2004, 236b and when I hooked up my grapple, no response from the aux. hydraulics. 1.Plenty of hydraulic oil. 2. Replaced the relays. 3. Disassembled the joystick and found the magnet destroyed. 4. I put a broken piece of a magnet between the small springs of the thumb wheel and it puts a load on the engine so I know the sensor is good. Do I need a specific magnet power for the 8 volt continuity? And should I be testing the ECM next?
Go back over the previous 7 pages and you should find values for the output voltage from the thumbwheel roller switch (check that you have the 8v supply to the switch by back-probing) with it in the centre, rolled fully one way, and rolled fully the other way. That is the first step to testing the switch function. Do not go any further until you can get the switch output correct. If you like you can put 12v on to each of the AUX solenoid valves one at a time (they are located on the main control valve - you will need the cab raised to do this) to check that the AUX function works in both directions when powered.
I did something a will never do again. I let my neighbor use my 257b and it ended up in his pond. The front was in far enough to have water run into the cab. Everything works but the auxiliary hydraulics. I pulled the ECM and the bottom of it was corroded enough to have eaten through he case. I opened it up and water ran out. Cat wants $6000 for a new one but I found one from China for $1000. They needed the serial number to program it so I'm hoping that it is okay. I had a tech from one of the local construction companies put his computer on it and it seems that the ECM is working. Could the water have shorted something and sent 12 volts to a sensor and burned it out? I've had the switch apart and it looks good.
If you go down the replacement ECM route DO NOT give the supplier the complete 17-character PIN from the plate, and especially not a photo. That is how PIN plates get cloned. The machine Serial Number is the last 8 characters from the PIN. In your case I'm guessing SLKxxxxx. Just give the supplier that information. From what you wrote above you have not conclusively established that the ECM is the root cause of the problem. If you pay $1000 for a replacement ECM and when you install it and the system still does not work, what then.? IMHO you need to do a LOT more troubleshooting before you condemn the ECM as being bad. Please start a new thread and give a Serial Number to get detailed assistance.
The old ECM was definitely bad. There was a lot of corrosion on the board and the water turned it into a slim that covered the entire thing it was pretty much impossible to clean it. I tried soaking it in alcohol and it didn't help. I have the new one in now.
And I'm guessing that the AUX hydraulic function still isn't working.? Is your neighbour paying for all this.? If not he darned well ought to be.
No unfortunately nothing
Post a Serial Number. You are going to require an electrical schematic. Also you need to be able to raise the cab because access is required to the main hydraulic control valve in the belly of the machine. Are you able to do that.? FYI, anecdotal experience of replacement non-OEM ECMs is that a fair percentage of them do not work straight out of the box and the supplier has to exchange them for another one. Bear that in mind.
SLK01727. I've done a lot of work on this thing and am very familiar with having the cab up. It's actually up right now.
Good to know. Check your inbox for an electrical schematic.
Well im going to point this out. It doesnt have a hole rotted in the box from one swim. Thats years worth of dirt and water in there. One of the worst ecm locations known to man kind
Those are my thoughts exactly.
See the illustration below. With the key ON and engine stopped apply 12v (and connect to ground obviously) to each of the solenoid valves marked 2 & 3 in turn. Can you hear them clicking as power is applied and removed.? CARE REQUIRED - With the engine idling BRIEFLY apply 12v to each of the solenoid valves marked 2 & 3. Do you hear the hydraulic system load up.? If it does respond correctly then for the next steps the cab will need to be lowered.
Got the email. Thank you so much. Now comes the diagnosis work. I have always prided myself in being able to fix everything myself. I hate the damage to my ego as much as the cost to have cat come out to look at it.
Do they run on 12 volts?
To achieve smooth modulation of the AUX function they work on a variable voltage supplied from the AUX ECM that can be anything up to 12v, but for the purpose of testing whether or not they respond to power you can apply 12v directly to them temporarily for a short period of time. What you can also do is locate the wires that supply the two AUX solenoid valves at the ECM end and, with the ECM connector unplugged, apply 12v to the machine harness from that point as well. Provided both solenoids click then you have also tested the wiring from the ECM to the solenoid valves. The Pin numbers are 40 (A1 solenoid), 58 (A2 Solenoid), and 42 (A Solenoid Source)
Thank you for the advice
The solenoids seem to be working fine. But I was jumping right from the battery. Where do they get there ground source from?
The supply to the solenoids is to a common pin on the ECM - Pin 42. Did you not see it on the electrical schematic.? Don’t get too far ahead of yourself at this point. If you tested by supplying power & ground right at the solenoids, both engine stopped and running, the next step is to lower the cab and do the same tests at the 70-pin plug on the AUX Hyd ECM. If the solenoids function as expected you have proved everything from the output side of the ECM as far as and including the solenoids. The next step is to prove the input side of said ECM, which includes the thumbwheel roller switch and the wiring from said switch as far as the input to the ECM.
Here's what I've found so far. The roller switch seems to be working. It is 4.18 centered 6.33 back and 1.92 forward. Checking the solenoids they have 9 volts to them all the time. Nothing changes to them when I move the roller switch. The ground coming out of the ECM seems to be nothing. I have to hook to to frame to get a ground to do any testing.
Those figures strongly suggest that the thumbwheel roller switch is good. Have you tested the same measurements by back-probing at the 70-pin connector at the ECM, just to eliminate the remote possibility that you could have a harness fault in the roller switch signal wire somewhere between the joystick and the AUX Hyd ECM.? If the thumwheel voltages at the ECM input give the same results as above you have confirmed that both the inputs and outputs of the ECM are functioning correctly. Therefore the replacement ECM is bad. Get hold of the supplier and have them send you a replacement. For non-OEM ECMs it's not an unusual experience. You're not the first person it's happened to and you likely won't be the last when rolling the dice on an ECM priced at $1k versus one at $4k. That's the common supply from Pin 42 on the AUX Hyd ECM vis wire L998. The AUX function is commanded in whichever direction by an internal connection within the ECM directing the voltage returning from the solenoid valve via either wire P978 or P979 to ground within the ECM in a modulated manner depending on the thumbwheel roller input signal to the ECM.
Before I buy a new ecm I was doing more checking and the is no power to no. 47 the lockout switch. Should there be?
Why should you.? You have checked everything else so the one that was supplied is obviously defective. As I mentioned earlier it's not unusual for ECMs from China. Have the supplier ship you another one. I assume you mean Pin 47 on the AUX Hyd ECM.? No there should not be power there. It's simply a continuity/connection signal between two points. The fact that you have all implement hydraulic functions except AUX indicates that the implement lockout switch and its associated circuits are working correctly. Try operating the lift or tilt and while you are doing that flip the lockout switch to OFF. Do the implements stop.? If they do then you have your answer.
This might help you to better get your head around how the implement lockout switch interacts with both ECMs.
Hey, I'd like to get mine repaired
Depends which type of thumbwheel you have. What model of machine did it come from.?
Somewhere in this huge thread I seem to recall a physically identical switch but it was designed for a 5V reference voltage. What do you think might happen if you simply put a resistor between Cat's 8V reference line into that switch, dropping that voltage to 5V?
What magnets did you use to replace the switch magnet? I have tried a magnet that is magnetised north to south on the flat surfaces. It works but only turns my attachment in one direction until I flip the magnet. Then only in the other direction. Any suggestions? Cheers
What magnets did you use to replace the switch magnet? I have tried a magnet that is magnetised north to south on the flat surfaces. It works but only turns my attachment in one direction until I flip the magnet. Then only in the Any suggestions? Cheers
Hey all, my aux hydraulics aren’t working on my new to me 247B2. Am I correct in understanding that as long as the aux hydraulic lines are hooked up, they should function when the thumb switch is rolled forward or backward right off the bat without having to press any other button sequence first?
That is correct. If the AUX hydraulics are not activating the first thing to check is the power supply to and voltage output from the thumbwheel roller switch. Somewhere in this thread will be a schematic illustrating the connections. Can't see a 247B2, only a B3 model. What's your machine Serial Number.?
Okay, thank you. My serial is MTL06131. When back probing the connector to test voltage, would regular multi meter probes do the trick or do I need special probes to test each wire? Also, is the magnet in the switch this round piece inside? I already took it apart to check. It was easier than getting the stubborn romps bolt nuts off.
It is, and it looks fine to me. Provided the probes are smaall enough to get in from the back side of the connector along the wire they will be fine. I've seen it done using a couple of paper clips pushed into the back of the connector. The tests need to be done without unplugging the connector. Measure between 1 & 2 with the key ON. The engine does not have to be started. Then measure between Pins 2 & 3 with the thumbwheel in the centre, rolled fully forward, and rolled fully back. Come back with your results.
A Hey Nige! Across - 1 and 2 I’m seeing 8v. Across 2 and 3 I’m seeing -7.5v regardless of what position the thumb switch is in. I tried this with just the key on and also with the key on, interlock bar down, and parking brake off. Same results.
That means the thumbwheel roller switch is farked, despite the magnet looking to be in reasonable condition. Between Pins 2 & 3 the output should be about 4.5v in the centre then increase/decrease by about 2.5v when you roll it fully one way or fully the other way. The only solution is a replacement joystick handle. The switch is not sold separately.
Roger. Luckily, I found a used one ebay that should be arriving today/tomorrow. The guy confirmed the thumb switch was working before removal so hopefully I didn’t get scammed.
I hope for your sake it does work because used handles seem to be like hen's teeth.
Tested the used joystick and it worked! The rubber coating on it is failing pretty bad, instant black sticky hands, so I removed the guts and replaced the ones in my joystick with them. Everything is back together and working fine! To help others, I kept my magnet since it was in good condition. If someone wants to try and replace theirs, happy to ship it to you. Just cover shipping. I’m assuming the hall sensor went on mine instead of a deteriorating magnet.
Hi do you still have the magnet? I will be taking mine apart tomorrow and I’m thinking that will be my problem. Thank you
I do. Shoot me your address and I can drop it in the mail.
Jeff Carvalho 14136 Hexam road Brooksville FL 34613 I can send you some $ through cash app or PayPal whatever is easier for you. Thank you
I did end up taking it apart and the magnet was crumbed in to pieces. So I’m pretty confident now the magnet will fix it. Thanks again
Hey man, totally had slipped my mind shipping it. But definitely will, sorry for the delay. I know it sucks having a machine sitting.
Yes thank you I could really use it, I appreciate it.
It’ll be there Friday. 9505 5158 3807 5189 8307 14. If you wanted to venmo $10 for the shipping, that be awesome. My venmo is @Jwhalen123 .
Got it. Thank you!
I just wanted to say thank you again you really saved my butt, I bought the machine not really knowing anything about cat skid steers, Thank you!
No problem! hope it works for you, I was in the same boat not too long ago myself.
Nige is hall efect
Yes indeed. I corrected myself later in the thread. Everything up to the early B-Series models had a Hall Effect roller switch. From the introduction of the B3-Series machines and all subsequent models the roller switch operation changed to a PWM sensor. See Post #12 on Page 1.
Thanks to all who contributed to this thread. I was able to diagnose and repair the switch in my Dad's 226B. Cleaning up the remains of the magnet gave some function back, but I ended up getting some diametrical ring magnets (9.5x5x3mm) off AliExpress. Made a tight fit hole in a bit of wood, pressed one in and cut in half with a Dremel and cutting fluid to keep it cool. Then epoxied into the switch. Works like new.
Nice repair
New guy here. Been reading all this info on thumb wheels, it is a lot to try and understand. Nige, is there any chance you might have a wiring diagram for a 242B. Serial number BXM01499. Would that fall under a hall effect or the PWM? I will have to "volt" out my wires. I have only test lighted them earlier. Will also check magnet in the handle, didn't have a clue what I was looking for before.
Your roller switch should be Hall Effect from everything I can see. Before disassembling anything, as a first step try testing the voltage on the signal output wire (P996 Green) at the connector under the joystick. Do this with the thumbwheel roller in the centre and then rolled both ways. Report your results. Electrical schematic on the way. Check your message inbox.
Mr. Nige, I wish to express my thanks for all your help. The handle was bad. After I got that fixed, then had a line that was bad. Got it all fixed. Can't wait to try it out this weekend, on something-anything. Thank you again.
do you have any pictures of your fix for the switch because i need to do that same repair.
been lurking here for a few years and finally got around to fixing mine. my hall sensor is working but the classic deteriorated magnet. i bought the diametrically opposed magnet linked before and got some magnetic viewing paper from amazon to ensure i had my poles set up correctly. i decided to go a new route and take out the little roll pin and 3D model the part and print a new one. i had some issues getting that fine of resolution from my pla printer, got a resin printer and tried printing it there but more issues (user error) so decided to go back and model the magnet holder in 2 parts so it could print flat on my bed and then i glued the 2 halves together in the jig (also modeled to keep halves aligned). then got the magnet oriented and glued in and ordered some 1/8" acrylic rod online from amazon and cut to length and glued in the through hole in the jig so that it was centered correctly (part isnt perfectly symmetric based on my measurements). i think it turned out well and getting ready to install and should fix my issue. pics, the fusion 360 file as well as the .STL file for anyone who wants to give this a try, feel free to use or adjust to your needs. thanks!
zip folder with fusion and STL files for anyone who wants to take a look
i am going to try this since i have been having trouble with positioning the magnet into the current switch, and i also tried the other 3d printed switch that was mentioned in this forum and that didnt work, i had to open up the hole for the magnet to go into and i had to bevel the corners of the rocker to fit in my sensor part. everything i tried with magnets i got either no response at all or i got some communication one way and constant communication the other direction even in neutral position. i ordered some neodymium Strong Countersunk Ring Magnet 1/2"x1/8 Rare Earth Neodymium 4mm hole, i dont know if the poles are going to work properly or if i have to get different magnets for it to work.
Nice job!
i have a 2005 226b model number is mjh00610 my question is can i re pinn the plug for the aux hydraulics and switch the hall effect thumbwheel for a momentary switch without any problems? please reply asap
Basically you are wanting to convert the thumbwheel into the optional 2-button control. What you have right now is this as regards the wiring setup. This is what you are aiming for. Note that the push-button signal wires are different wire numbers to the output signal from the thumbwheel roller. The return wire P997 is the same for both setups. IMPORTANT: There is one other change that is required to make this conversion work. The software settings inside the AUX Hydraulic Control (ECM) will need to be changed from "proportional thumbwheel roller" to "switch to ground". I may not have got the titles 100% correct but that's the gist of it. To make this change will require the use Cat ET diagnostic software.
so what you are saying is that I still have to reprogram the ecm? I looked it up a few minutes before I asked about the conversion and is sounded like I didn't have to reprogram the ecm as long as the momentary rocker switch worked the same. because I am looking at using a momentary rocker switch since I am having trouble sourcing the right magnets to use for any repair because mine had the dissolved magnet problem, and I cannot afford a new switch right now as I don't have any income.
Not so much reprogram, simply change one parameter in the ECM Configuruation screen. No passwords or trickery involved, it would only take a couple of minutes. The unfortunate thing is that it will need ET to do it.
ok thanks, I appreciate your answers. how would I put a new magnet into orientation for the thumbwheel to work if that is how I go? because finding the right magnets is difficult. I have some old electronics I could maybe get some magnets out of however I don't know how to figure out the polarity
I suggest that you need to get in contact with HEF member @quiksilvr via private messaging. He was the guy who started this magnet repair business off right back on Page 1. IIRC at one time he was offering to install replacement magnets in thumbwheel roller switches for forum members.
ok.