Just recently bought an 07 cat 262b skid steer off someone on facebook. Has a 4n1 bucket on it but when trying to test out the aux buttons on the joysticks nothing happened. Guy claimed he thinks it's just a bad joystick switch. Bought it anyway but trying to troubleshoot it myself. When I took the panel under the seat off to check the fuses I noticed there is only one fuse block. Just looking at the picture diagram on the plate and doing some vague internet research it seems to me like there should be a second fuse block there. Sorry if it's a dumb question but not super skid steer knowledgeable. Isnt there supposed to be a second block there that makes the aux work or no? If not does anyone have some troubleshooting input on what to check over? What all aux connections there are and where at? I have a schematic and am a decent mechanic but am no electrician. Under the floor plate both ecms are there but under the seat ustst one fuse box. Is that second fuse box supposed to be there for the a1 and a2 to work or am I missing something else? Is it possible it was taken out before selling it? I know cat parts are pricey. Seemed like an honest guy at the time and but you never know anymore. Does anybody got some knowledge to throw at me?
Question - machine Serial Number..? Also what Cat document reference electrical schematic are you using..? With the S/N and that reference I could at least tell you if you're using the correct schematic or not. It would also enable an answer to be provided regarding your fuse panel question. Do you have (or can you get hold of) a digital multimeter and are you familiar/competent with the process of measuring continuity in a circuit.?
S/n is PDT04800 and the schem Im looking at is 216-6423. And I do have one and somewhat yes. Also looking at the joysticks they don't look to be original to me. The one you use in your left hand is gray and has two buttons vertical and a trigger. Trigger is stuck. The one you use in your right hand is black and has two side by side buttons. I tested the two buttons with a test light on the right and both button switches are working. Where do I go from there? Is there supposed to be a roller button to open and close the grapple part of bucket of how does that work?
You have the correct schematic for your S/N. At least that answers that question. Next question - do you have an operator manual for it so that you understand the the functioning of the various controls.? The Cat Publication reference is SEBU7731. https://www.ebay.com/itm/CATERPILLA...Owner-Operator-Operation-MANUAL-/202525427640 Be aware that you can biuy a brand-new on in pdf form for $49, or $57 in paper form. Regarding your question about the handles maybe being non-OEM. Can you take some photos and post them up here so we can all have a look.?
Lefthand
And right-hand. I do have the original owners manual I found in the cab. But since they cover multiple model option controls and such, things are hard to pinpoint. Reading the book it seems just pushing a1 would open the grabble bucket and a2 to close. If I could find out the all the original options and stuff off the s/n possibly having the correct joysticks would make it work? Also the machine has a few other issues, fuel gauge not working being one of them. Maybe a correlated issue? And the electrical connection for the worktool attachment I can't seem to locate. Going off the schem it looks to me like it would be part of that second fuse box and some harness assemblies that aren't there. Again making me think there mightve been some parts taken and swapped after finding a number of little issues that I wasn't informed of starting to surface but Im just not familiar enough to know..
I forgot to add that there is a hydraulic light on the dash that's been on since I bought it. Hydraulic filter not functioning correctly indicator light. Assuming it's just way overdue to be changed. That and the autolevel box has a leak and needs addressing, as it also doesn't work. Solenoid looks cooked. I haven't been operating the machine, just trying to figure out all the bugs before draining and replacing all the hydraulic fluid and rebuilding the leveler box successfully I'm hoping. Like I said the machine has a handful of issues.. could the fault light be stopping the auxillary function? It's certainly a project machine, but all I can afford in hopes to fix.
I would say both joysticks are genuine Cat. The grey one will be a later replacement for the original black one. The stickers next to the controls are a reliable reference for what options the machine was shipped with and what the various switches should do.
Cherry-picking your post a bit here. Your machine was not built with a Work Tool attachment (it's an option) so you will be missing the 2nd fuse box and the all the associated harnesses. Regarding the press-button switches on the joysticks the easiest way I can suggest to test them is to disconnect the wiring harness right below the joystick, get the probes of your DMM on the appropriate pins, then press the button and observe if the circuit goes from open to closed and back again as you operate the switch.
Ok that makes sense then. And I have done that, and the switches do go from open to close. Where do I go from there?
I would trace the wires backwards on the schematic from the connectors under the joysticks to the next main harness connector - if there is one between and the ECM. Open up that connector, or the ECM connector if there isn't another one, and check that the circuit is behaving in the same way as it does at the joysticks. if you have not had the cab floor up yet to get at the ECM you might be in for a bit of a shock. It will probably be buried in mud, and if it is your electrical contact issues might well be in the ECM connector. At least I hope so.
I do have it all opened up and there is lots of dirt caked on everything. I will clean it and try to check there. Hopefully it's something simple. I appreciate all the knowledge. I noticed your profile says your from granville? Is that granville ohio by chance? Lol
Go to your local parts house and buy a case of aerosol electrical contact cleaner. You'll need it before you're done....
So I've come to the conclusion that the joysticks on my machine are "cat oem" but they are not the original ones. The previous owner worked on it themselves as opposed to taking it to a dealership for servicing. That being said I don't think they were ever calibrated through the cat et when they were replaced. All the wiring and everything seems to be correct but the buttons won't work unless theyve been hooked up to the et and recalibrated to the ecm right?
I'm not sure the buttons require calibration. They are a simple On/Off mechaniism. Are the switches under the buttons opening & closing correctly when you press & release them.? To my knowledge the only thing that should be calibrated when a joystick is replaced are the position sensors whose signals change when the joystick is moved forward/back or left/right.
Yes they are
I just changed handles and no calibration was needed.
But the buttons are not simple on/off buttons there is a circuit board in the handle.
I just got the special probes in to test the harnesses so I'm going to do that. But I went through all the grounds and redid them all so they should be good there. But even the horn button doesn't make the horn work. And that's a pretty simple a to b circuit I'd think. Like I said they're definitely not the original ones to the machine and all the buttons not doing anything just seems odd. Which is why I thought maybe they did have to be messed with through the computer
I had an old handle laying around the shop and went to take a picture for you but apparently I threw it out when I cleaned the shop last week. The buttons are variable displacement, and the circuit board in the handles, has to do with the variable potentiometer to control the valve and they wear out. I went through what you are doing, finally decided to change the handle, after I ripped the old handle apart to see what was inside, so at that point it was junk.
Ahh I see. Well I did notice before that the wire colors from the handle to harness plug are opposite of each other. Like the right one is where the left one should be and vice versa. I thought it was just on off switch style so didn't think anything of it.. maybe I'll go try to switch them and see what happens
Your right handle doesnt look like a B handle, it looks like a handle for an A model
The new handle will have a rocker switch.
No change. So youre saying I need one with the rocker switch that's the issue?
That's what the guy that sold it to me said he thought but looking at the picture on the side of the cage just shows the two button style. I wish I knew what all the original options were on this thing.
I’ll have a dig in SIS tomorrow and see if it shows some clear views of what the original joysticks were supposed to look like. So from the electrical schematic it appears as though there are three different types of control handle/button/roller arrangement. By your Serial Number the LH Handle Assembly on your machine should be a 218-6117, the RH handle should be a 218-6118. Are there any tags anywhere to indicate the Part Number.? They are often located on the wiring harness. As you can see from the diagram below these are the simplest of the handles. One has two ON/OFF push-button switches, the other has only one. Nothing to calibrate in those switches, the contacts either close or they don't.
If you look at the circuitry on the first picture it would apear to be a variable potentiometer.
Is there a Part Number marked anywhere on that unit.? It can often be on a plastic tag attached to the wiring harness close to the connector underneath.
Update - had a friend of mine that has access to et plug into the machine. He was able to switch the joystick configuration from "pwm" to "switch to ground". So now my auxillary buttons are working and my 4n1 bucket opens and closes like it should. However on et it was only detecting the auxillary ecm, but not the interlock control ecm. Any idea why it's only picking up the one? The fuel gauge doesn't work and I don't believe the charging system is either.. I would think being able to read the interlock ecm could help figure out why but it doesn't come up on the computer. What connects the two ecms together or any ideas on why this might be?
What version of ET was he using..?
2019 a I think
That should be new enough to recognize both ECM's. I was concerned he might have been using a much older version of ET. If it was a "full fat" (dealer) version I hope he tried connecting via the ATA Datalink as well as the more normal CDL. I've seen a number of cases over the years where an ECM wasn't recognized on CDL but was on ATA. The usual reason is a fault in the CDL wiring somewhere in the branch of the machine wiring harness feeding to the ECM that won't connect, sometimes even condensation or corrosion in the harness plugs right at the ECM. Has the ECM been changed since you got the machine, or maybe did the previous owner change it.? That's the only easy way the Config could be changed, or unless someone was in there messing with ET without understanding what they were doing of course. Do you have the Electrical Schematic.? That would help you to identify the "branch" of the main harness that takes the ATA & CDL wires to the Interlock ECM.
Forgive my ignorance but how do you connect via ATA datalink vs CDL datalink?
I have not changed it nor do I think it has been before.. and I do have the schematic. I see CDL wires on it but nothing labeled ATA. I see CDL + and - directly on the auxillary ecm. Not on the interlock but looks like those wires connect in one of the large connectors. 944 and 945. Purple being aux and striped blue interlock..
The ATA Datalink is the one used for flashing software into an ECM, at least it is on the machines I've worked on. It uses an application in ET called Winflash, but this is only in the dealer versions of ET and not the customer version. However having looked at your Electrical Schematic there is no ATA Datalink present, so I'm at a bit of a loss to explain how ECM software gets updated on that machine. Also as you pointed out there is no Datalink connection to the Operator Interlock Control therefore ET won't "see" it when connected. Quite how that affects diagnostics I have no idea, maybe someone else knows. This is strange, because the only way I know that those settings can be changed is by someone going into the ECM with ET and changing the values associated with those particular parameters related to the joystick controls.
On these early machines, ET is only used to diagnose the auxiliary hydraulics ECM. Troubleshooting the interlock ECM is done by observing the status of the seatbar and parking brake lights. If you buy a new/reman interlock ECM, it comes pre-programmed.
A 21st-Century version of an EPTC-II or an ADEM-I ECM then..?
plus ça change
I was kinda thinking the same thing. I stil have nightmares even now about re-chipping some 300 EPTC-II boxes when we had the famous 6th to 1st engine overspeed events.
Ok good to know. Thanks y'all for all the knowledge, much appreciated. One more question.. hydraulic fluid and engine/drive chain box oil. I'm changing all of it. Do I spend the arm and a leg to get it all through cat or is there an equal alternative you could recommend?
Whatever from a major oil company meets the spec in the O&M manual. Doesn't have to be Cat-branded oil unless they have a special offer on that makes their oil attractive price-wise I assume you do have a manual..?
Ok I figured so, just wondered if you had a good go to brand. But yes I have the manual
I’ve used Mobil, Shell, & ConocoPhillips in the recent past with good results. Total also seems to be good but I have no long-term info on it. I guess it all depends which company’s products are available in your area.