Hi guys and gals. I just purchased a 2014 259d with 1200 hours on it. Machine is in great shape for the age and runs great. I picked up a grapple today, but I can’t figure out how to get the Aux hydraulics working. I understand the thumb wheel on the right joystick opens and closes the grapple. But it is dead. No response whatsoever. Hookups are good. I checked all the fuses in the cab. They are all fine. Keep in mind I don’t have a ton of experience with equipment so I may be doing something stupid. I tried every combo of buttons etc but to no avail. Any suggestions?
Machine Serial Number.? Then I can get into the correct Operation Manual and give you proper instructions.
Serial number is CAT0259DKFTK00414. Let me know if you need any other info. Thanks!
Question: When the grapple fails to work from the thumbwheel do all the other hydraulic/hydrostatic functions still work.?
Yes. I can still drive, steer, raise/lower and tilt bucket.
For what it’s worth the guy I bought it off said he had a post hole auger on it last summer.
It appears as though simply rolling the thumbwheel back and forth should open & close the grapple. See attached. When you roll the thumbwheel can you hear any change on the engine RPM.? If you can't hear any change do you have a multimeter capable of measuring duty cycle.? You will need one to measure the output of the thumbwheel sensor. Whatever the result of the issue you have right now I would suggest getting hold of a manual for the machine, especially if you are going to maintain it yourself. Here is a genuine manual on CD, and cheaper than you can buy it from Cat - https://www.ebay.com/itm/304863216246?hash=item46fb438276:g:KZEAAOSwEWJkJGNm
Thanks for link to manual. No rpm change when using the rocker switch.
In that case a test of the output of the thumbwheel sensor would be the next step. As well as the appropriate multimeter you'll need some test leads that permit you to get up the outside of wires into the back of harness connectors, commonly known as "spoons". Google Cat 7X1710 (other options are available) which will give you an idea what they look like. The sensor is a PWM type which is why it needs a meter with duty cycle capability.
Ok. Thanks for the help. I’ll let you know how I make out.
If you have, or can get hold of, the appropriate type of multimeter the duty cycle for the thumbwheel sensor should be as follows: - Centre approx 50%, rolled full one way over 85%, rolled full the other way less than 15%.
I pulled the thumb roller apart. Magnet still looks good. It may be a power issue. Possibly not getting power to the switches at all
I'll send you an electrical schematic. Keep an eye on your messages. EDIT: When you're checking the power supply to the thumbwheel with the key switch on, it should have 8v DC +/- almost nothing because it's a stabilized supply created inside the ECM. Measure voltage between the wires P769 & P770 marked "roller power" and "roller ground"
Ok so I pulled the right armrest apart to get at the wires, located the 12 pin connector and tested the voltage across roller power and ground. It’s right about 7.88v on my cheap multimeter. When I connect 1 and 2 with a jumper wire for a second I get a reaction from the machine. RPM goes up like it’s building pressure. At this point is it safe to say it is my switch even if the magnet inside still looks good?
I stand corrected. You have a Hall Effect thumbwheel not a PWM type. Connecting Pins 1 & 2 is simply shorting out the power. Are you sure you didn't connect Pin 1 to Pin 3 which is the roller signal output.?
I connected the same pins I measured for voltage and got the 7.88v. I am using the machine now but will pull it apart later to double check.
In that case all you did was short the power and ground to the thumbwheel. I'm not sure I would recommend shorting the power wire to the signal wire because the switch output is only around 5v IIRC. Putting 8v down that wire could fry circuits in the ECM and that could potentially prove to be extremely expensive....... If you want to do a bit of reading on the thumbwheel, try this thread. You can check the switch function and output. If necessary I suggest to PM @quiksilvr - HeavyEquipmentForums
Here are the voltages I got when testing between the wires and working the switch. 8v between white and brown. No reaction with switch 5v between white and yellow. Will go up to 5.3v with switch down and 6.1v with switch up 2.8v between yellow and brown. 2.5v-1.81v switch up or down 8v between white and purple. No reaction from switch 2.8v between yellow and purple. 1.8v to 2.4v when going back and forth with switch 0v between brown and purple and no reaction from switch. Thoughts?
OK, here's the problem. The pigtail wires from the switch to its connector seen in your photo are not shown on the schematic. So I have no idea which wire corresponds to what. Can you check the voltages (with the key ON) on the three wires on the machine harness side shown in the snip above. They are Pins 1, 2, & 3 of the 12-pin connector. The Pin Numbers are moulded on to the back of the connector on both sides. Should be: - 1. Between P769 Yellow and P770 White - 8.0v. 2. Between P996 Green and P770 White - somewhere around 5v with the thumbwheel in the centre and approximately 0.8v above or below that depending which way you roll the thumbwheel.
8v between 769 and 770 2.8v between 996 and 770. 2.5v-1.81v when I move switch up or down
Switch is foobarbed somehow. The output voltage is way down in all positions. The unfortunate part is that the switch is not sold separately. You have to either repair it or buy a replacement handle.
Part is ordered. I will let you know how I make out.
What exactly did you order.?
This one right here.
Part is installed and life is good. Really appreciate the help!
It’s just a shame that the switch is not available separately when it’s so easy to remove from the handle.
Yeah it really is. Especially when you can purchase most of the other switches separately. Just not this one.
Is there any other writing or numbers on the switch? I doubt Cat made it. If it could be traced back to the supplier, perhaps it could be bought that way.
We’ve been here before……. There’s a whole thread on it. There are switches that appear identical but the difference is that they operate using a 5v DC supply. The Cat switch operates on 8v and so far nobody has come up with a replacement that is available on the open market.
I like a challenge if he'll send me the switch, It's already broken. What could possibly go wrong? I have a bench top variable DC power supply next to a 4 ch oscilloscope and enough multimeters to supply a small classroom. Can the thumb wheel/switch be tested out of the joystick or must it interact with something else in the handle and be tested as a unit. Can you post a link to the thread relating to the 5 volt version. How much money was the 5 volt version? I'm in the mood for mad scientist. Color me interested
See the thread I linked in Post #17 on Page 1. It might fill in some blanks. The switch doesn’t have to interact with anything else. Simply supply 8v to it and measure the output voltage as the roller is moved. There is a snip from the electrical schematic on Page 1 also. The 5v version was around $100 IIRC.
No numbers to speak of on the switch itself. Message sent. I will mail you the switch.