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Aux. hydraulics

Richard Marion · 2021-02-24 17:52

Hello and good day , I have an issue as where my thumbwheel just does nothing all of a sudden . The machine is a cat 216b all other systems work just fine , It has not been used in a few months but used to work fine with the auger attachment . Is there a common issue where i can look first , A wiring diagram would help plenty . Thanks from georgetown ontario canada.

Replies30
  1. #1Nige2021-02-24 18:28

    To obtain an electric schematic would first require a Serial Number. Too many options out there (7 acksherley) to go guessing.

  2. #2Richard Marion2021-02-24 20:10

    Yes I should have put that in there CAT0216BCRLL10172

  3. #3Nige2021-02-24 20:16

    Sent you a PM.

  4. #4Richard Marion2021-02-25 15:38

    Is there a troubleshooting guide for this machine available to do a step by step test on the aux hydraulics . I want to fix it not bypass it if i can .

  5. #5Nige2021-02-25 16:41

    No troubleshooting guide per se. Most mechanics would test the system based on the Schematic and knowing how the various components work.

  6. #6Nige2021-02-25 18:27

    As far as I can tell the Handle As on the RH joystick of your machine should be a Part Number 215-8307. Below is the illustration of it taken from the electrical schematic. With everything connected and power on you need to back-probe the wires at CONN 33. You should have 8V between P994 & P997 if the power is working correctly. If not you have to go back to the ECM (Grid D-1 of the schematic) and check for power there. I hope one of our skid-steer experts will chime in with how to test the signal from the thumbwheel on wire P996. I think it may be a PWM signal but I'm not certain of that. (If it is then you will need a DMM that reads % duty cycle.)

  7. #7Richard Marion2021-02-27 15:57

    I have checked wire p994 and have no power to thumbwheel , can I run a wire to solenoids with grn and yellow to a momentary on off on switch and call it a day . and eliminate factory activation .

  8. #8Nige2021-02-27 18:52

    What are you using as a ground connection when you check P994.?

  9. #9Richard Marion2021-02-27 19:04

    I used the chassis during this test, !!!!! Do I need to use p997.

  10. #10Nige2021-02-27 20:38

    Yes you do need to use P997 because it is the sensor return wire to the ECM. See the snip from the schematic that I posted above. If you have back-probe attachments for your DMM you can try measuring the voltage between P994 & P997 at CONN 33 both with the harness connected and also disconnected to see if it makes any difference.

  11. #11Richard Marion2021-02-27 21:49

    Thank you I will test again Tomorrow .

  12. #12Nige2021-02-27 22:25

    I think the voltage should be 8.0v +/- 0.5. You can confirm that if you follow wire P994 back to the control on the schematic. The terminal it’s connected to will probably be labelled something like “+8v sensor power”.

  13. #13Nige2021-02-28 08:22

    Because the power is supplied from the ECM you will need to test with the key ON.

  14. #14Richard Marion2021-02-28 19:37

    Yes got to play again today , tested 994 blue + and 996brown - and got zip , I have the machine apart but need to take outside as i dont have the height inside to raise cab . I did get it outside fri. but only got it washed in there . Can i do a stand alone switch to activate these , seems easy enough and bypass ecm .

  15. #15Richard Marion2021-02-28 19:42

    In that pic of the wires I see an orange that connects in the drawing is that pressure relief , so green and yellow would be my new favorite friends right .

  16. #16Nige2021-02-28 19:45

    It didn’t make any difference with the machine harness connected or separated at the joystick connector then.? TBH the next move really ought to be to check continuity in those two wires between the machine harness CONN 33 and the ECM. It may be nothing more than a broken wire which will be a far easier fix than trying to McGyver a complete new control circuit. I realize that to test that you will have to raise the cab, but you’d have to do that anyway if you went the McGyver route so it’s as broad as it is long IMO.

  17. #17Nige2021-03-01 09:46

    Looking at the schematic there is another connector (CONN 27) between CONN 33 and the ECM. I suggest to disconnect the machine harness both at the Auxiliary ECM, at CONN 27, and at CONN 33, then test as follows: - 1. With Key on, test for 8.0v DC between Pin 60 "Proportional 8v Supply" & Pin 52 "Proportional A Snsr Return" of the ECM. If you find 8v there then proceed to step 2. 2. Check the continuity in wires P994 & P997 between the ECM and CONN 27, and also between CONN 27 & CONN 33. 3. Clean all connectors with aerosol contact cleaner before reassembling.

  18. #18Richard Marion2021-03-01 16:04

    I will check tomorrow , I cannot find an ECM anywhere on this machine I believe its a 2009 all engine controls are mechanical just electric shut down of course . I will do a good thorough trace of 994 and 997 when i move to an area with higher ceiling .

  19. #19Nige2021-03-01 16:45

    There are actually two of them - located under the floor. See below. The operator seat will have to come out first, followed by the floor panel itself. You will probably be horrified how much mud and general debris you find in there. TBH that's most probably where your problem is.

  20. #20Richard Marion2021-03-01 19:19

    Damn thanks I will dive in there tomorrow , Thats a great pic thanks a bunch .

  21. #21Richard Marion2021-03-01 19:27

    I found some stumps and boulders in that area under the seat lol.

  22. #22Nige2021-03-02 08:05

    No dogs or small chidren to go with them..?

  23. #23lantraxco2021-03-02 12:15

    Gotta love engineers....

  24. #24Richard Marion2021-03-02 14:50

    Well I dove in deep today , removed floor and cleaned up area pulled all connectors apart cleaned and tested all and checked supply to ECMs all checked out fine , reassembled hooked up battery tested harness where joystick plugs in still nothing then out of the blue BAM 8 volts on the blue 994 cool i thought i had it , so i shut down machine hooked up stick checked and nothing unplugged again and back to no voltage at 994 , i am thinking the ecm is at fault , i also did some tests on the aux solenoids and the system worked great on jumpers just a bit fast moving .

  25. #25Nige2021-03-02 15:12

    Somewhat good news. I suggest that you might try to find a way to measure the 8v at the ECM to detect whether you re losing the voltage there (ECM faulty in other words) or whether it is disappearing between the ECM output pins and the joystick input connector. What did the ECM connector (and all the harness connector) pins look like.? Any visible greenery or were they nice bright & copper-coloured.? Any signs of damp around the flanges where the ECM bolts together.? (It's in 2 halves). That's the purpose of the graduated PWM signal output from the thumbwheel on the joystick, to dampen down the response.

  26. #26Richard Marion2021-03-02 16:37

    I will get a reading of output at ECM , and I am going to try a resistor in the jumper power tomorrow see if i can tone er down if I go that route . The connectors were in great shape just a little dust in the other ECM plug .

  27. #27Richard Marion2021-03-02 16:50

    I might bump 12 volts down to 6 and send that to the original thumbwheel from a source other than ECM and see if it reacts , maybe alls ok accept the 8 volt ECM output .

  28. #28Michaelarjune2025-09-13 00:01

    I’m having the same problem I bought a new joy stick and still nothing I read somewhere that if you jump the seat sensor it disables the aux control? Is this true does any one have a diagram of the fuse box and relay ..?

  29. #29Nige2025-09-13 04:04

    I think you might be better served by creating a new thread. Start with the machine Serial Number and give as much information as you can about how the problem developed.

  30. #30Michaelarjune2025-10-06 22:16

    Ok I will thanks