The part number on my coils seems to obselete (155-4426-04 on one side and CAT 4278 on the other) and Cat parts can't seem to cross reference, worktool switches quit working and continuity on both of these coils was like 2.0 when I've read it should be 10.5 or something, how can I find these parts, these are the two solenoid valves on the block under the seat on the back right hand side, we traced the wiring harness to?? Help!!
Is this the valve you're looking at and are the two solenoid valves in question the two sticking up out of the top laft side..?
Yes front and back coils are what we traced the switches back to. I can check resistence again but was around 2 I think had just read another forum it should be 10??
Have you removed the complete solenoid valves for a look.? I traced it both ways. The two valves in that illustration are identical. The 155-4426 Part Number of Coil As services to latest Part Number 323-9533. Is there a Part Number on the valve body anywhere.? The complete Valve As is listed as a 185-4254 and the Coil As for that P/N is listed as 323-9533. So whichever way you slice it 323-9533 is what you need if in fact the Coils are actually your problem, and somehow I don't think they are. The resistance specification of the 323-9533/155-4426 are the same - 2.2 ± 0.2 ohms. So your solenoid coils are measuring correctly.
See the Table on the bottom of Page 8 of the schematic.
Maybe it's time to start checking the wiring for continuity and the AUX switch on the joystick if you haven't already.?
Checked switch will check wiring again! Will pull valve and find part# Schematic very helpful thank you for that!
I can't recall which one works which but to engage AUX functions don't you have to press and hold one switch then press a 2nd switch.? One of the switches gives the "engage AUX" signal to the ECM and the other one the "hold" signal.
Hadn't been using the finger button it may have been a hold, I had been just holding the thumb roller switch forward to turn one way and back to turn the other. Used it primarily on log splitter, trencher and flail mower attachments and another homemade roller attachment we use to roller up row covers. As long as the park switch was engaged auxiliary hydraulics would work. It started acting up when it would not start forward until you would run it backward, at first seemed a bit odd. Maybe a valve starting to stick?
It could be the roller switch. They are a Hall Effect switch and the magnet has a habit of falling apart. Use the schematic and measure the switch input which should be 8v IIRC. Then measure the output in the centre and rolled full in both directions. Centre should read about 5v and about 0.8v more or less depending on which direction the roller is moved. Post back with your measurements.
If you want to know all about the RH joystick thumbwheel roller switches on the early (A & B models) Cat skid steer Product Line, fill yer boots - Thumb Roller If your switch has gone U/S then unless you can repair it, replacement is going to cost you a complete joystick handle because Cat don't sell the switch separately.
Hi, I'm looking for a replacement joystick with the thumb roller. Anyone know that part number?
For what model.? Post a Serial Number please. Have you tried repairing your thumbwheel roller switch using the link posted above.?
Input to switch is 7.99 v, center out is 3.600, roll forward out = 6.01 roll backward= 2.235 voltage at coil is constant 4.25 no matter switch position, bout the same with new or old switch, pic of the valve seals seems ok not sure how else to tell if they are bad
Those numbers sound not too far away. It's hard to say for sure because there is no specification for the output values. The switch output goes to the ECM. The next step would be to check the wiring between the bottom of the joystick and that location. So you would be checking continuity on wire P996 Green marked "roller signal" between the 12-pin connector on the bottom of the joystick and Pin 53 on the Aux Hydraulic ECM marked "Proportional Signal". It may also pay you to measure the voltages at the same ECM Pin 53.
On receipt of the input voltage on P996 Green the ECM then sends out an output voltage to one or other of the two Aux solenoid valves on either wire P978 Green (from Pin 40) or P979 Yellow (from Pin 58). Both solenoids use a common return L998 Orange (to Pin 42).
Valve body for above part# 185-4254 pic on Cat part site doesn't show threads, just not represented in parts pic? Also seals are in slightly different versus upper ports??
No idea, but illustrations are often generic and are not guaranteed to accurately reflect the actual appearance of the part. But until you verify that the ECM is receiving a varying voltage input from the thumb roller switch as it is rolled back & forth, and that varying input voltage is not resulting in a fixed output voltage from the ECM then my suspicion is an internal problem in the ECM. The solenoid valves are way down the diagnostic line at the moment. Have you tried applying 12v direct to the solenoid valves.?
The ECM IS receiving the voltages list in earlier thread, we have continuity from ECM to solenoid valve, but only a constant 4 v to each valve with no change with roller switch position. Will try appying 12 v to valves directly next.
You can probably find an equivalent coil and valve from Eaton: https://www.eaton.com/content/dam/eaton/hydraulics/valves/valve-documents/SiCV Catalog_Section A.pdf It doesn't sound like the solenoid and valve are the problem though. Are you able to open the ECM and look for burned out components?
If it does come down to the ECM I would suggest to enquire about any Reman option first. If there is a Reman option and you open up the ECM you can kiss the Core Credit goodbye. It will not qualify by virtue of the fact that it has been opened. There are also companies that repair ECMs.
The Aux Hyd Control ECM is Part Number 216-0658. There is a Reman available P/N 10R-5613 that is unprogrammed. It would have to be flashed by a dealer in order to work. So not plug & play.
I am having the same issue. We took out the valve and plugged the valve body and turned the machine on, and we are not getting any flow into the line for the coupler for the work tool in the valve body and self the line next to the solenoid valve.
You'll need to be a bit more specific about exactly what the problem symptoms are, and also supply a machine Serial Number. Remember this thread was started by a person looking for a Part Number....... I'm struggling to imagine how you "took out the valve and plugged the valve body" unless you supply some photos or some more detail.
Serial number is CAT0216BHRLL01557
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