Working on my 247B Serial:MTL03866 It came to me from a equipment grave yard and has been quite a process to get into reliable shape, but I am getting there. Recently I ended up with a operators manual and realized that the "Auxiliary Override" light that has been on constant in my machine is a setting to run the hydraulics with the lap bar raised. I wanted to turn the light "off," so tried the step to roll the rightside joystick control up and down while pressing the left lower button the left side joystick. I did not see any change, and chalked it up to being odd. Then, I went to run my auger and had no Hydraulics at all! So I messed with it, and found some posts here to check the voltage on the right side joystick roll switch and my numbers are all out of wack. I have 8 volts in, and on the out have 4.32V at the center, 2.0V Forward, and 6.3V rear, that means replace the switch? So, I tore the switch apart and cleaned it, and see the magnet is cracked in a few places. Then the hydraulics worked, then didn't, and now do. I have not had any issues with my seat and lap bar safety switches, they work and the appropriate lights work. The wiring harness is unmolested, this was/is a clean machine. Do I need to replace the joystick? How do I turn off the Override light?
This is the Override switch, and corresponding light being referred to: This lights has ALWAYS been on, I can not get it to turn off.
This red light turns on when the Override switch is pressed "UP" disabling the hydraulics, functions correctly. Orange light on as always..
I wouldn't say so, maybe others would. The output is a proportional voltage that is "minimum" rolled all the way one way, "maximum" rolled all the way the other way, and somewhere halfway in between those two values for the centre position. At 2.0v one way, 4.32v centre, and 6.3v the other way the output from yours seems to be performing pretty much the way it should. I saw (measured) figures somewhere else of 5.72v at center, 3.93v forward full travel and 4.94v reverse full travel, so who knows.? There is no specification that I know of for the voltage output from that roller switch.
Sorry, missed this before. I'll send you an electrical schematic. You may need it. From the Operation & Maintenance Manual SEBU7732 which you really should get because it will pay you many times over. (Is that the one you have.?) Switch (Hydraulic Lockout) and Switch (Interlock Override) Switch - Hydraulic Lockout and interlock override The switch is located on the right headliner. Depress the top of the switch in order to activate the hydraulic lockout. The switch tells the auxiliary hydraulic ECM that the operator wants to disable the auxiliary hydraulic circuit and the high flow control. The switch also tells the interlock ECM that the operator wants to disable the work tool. The switch is a normally closed rocker switch. When the switch is actuated the circuit is open. When the switch is actuated, an open is placed on pin 47 of the auxiliary hydraulic ECM. The work tool will be disabled. The auxiliary hydraulic ECM monitors the status of the switch. No diagnostics are associated with the switch. The interlock override switch is located on the right overhead control panel. The interlock override and the hydraulic lockout share the same switch on the machine. See illustration 8. Depress the bottom of the switch in order to activate the interlock override. The switch tells the ECM that the operator wants to be able to raise the armrest in order to exit the seat while the continuous flow function is active. The switch is a momentary, normally open rocker switch. Pressing the switch puts a ground on the pin 64 of the ECM. The auxiliary hydraulic ECM monitors the status of the switch. If the input is grounded for 30 seconds or more, the ECM will interpret the signal as a stuck switch and the ECM will produce a diagnostic code.
Thank you! I received manual SEBU7732-09 It was tough to find but appears to be the correct one? BTW, here was what MY ECM's looked like just a few weeks ago, after about a year of ownership and getting the thing back on it's "wheels"
After cleaning:
The first time I saw the machine, it has been a lot of work!:
The latest version available online is -11 compared to your -09 version but the basics should all be the same. The extract above was sucked directly from version 11. "It was tough to find" - Say what now.? The manual can de downloaded in pdf form from Cat Publications in 5 minutes or less. https://catpublications.com - search for SEBU7732. I know. The location of the ECMs under the floor wasn't the brightest idea Cat ever came up with. It's fine if people take care to keep the space under the floor clean, not so good if they don't. I sent you an electrical schematic. Having seen the "before" photo of the ECMs it might pay you to actually start checking out continuity on wires and also that the switch is working as it should. When you press the bottom half of the switch to engage the Interlock Override all it's doing is momentarily connecting Pin 64 of the Auxiliary Hydraulic Control ECM to machine frame Ground. Maybe something is amiss and Pin 64 is permanently seeing ground.? T'is not witchcraft............
Depress the top of the switch in order to activate the hydraulic lockout. (THIS WORKS) The switch tells the auxiliary hydraulic ECM that the operator wants to disable the auxiliary hydraulic circuit and the high flow control. The switch also tells the interlock ECM that the operator wants to disable the work tool. The switch is a normally closed rocker switch. (THIS SENTENCE MAY BE BACKWARDS, 1&2 ARE NORMALLY OPEN, 2&3 ARE NORMALLY CLOSED) When the switch is actuated the circuit is open. When the switch is actuated, an open is placed on pin 47 of the auxiliary hydraulic ECM. The work tool will be disabled. (PIN 47 IS THE GREEN WIRE @ THE SWITCH, WHICH IS PIN 3. WHEN THE SWITCH IS OFF PIN 3 HAS CONTINUITY TO GROUND, ACTIVATE THE SWITCH AN IT OPENS. THIS FUNCTIONS CORRECTLY AND SHOULD BE GOOD TO THE ECM) The interlock override switch is located on the right overhead control panel. The interlock override and the hydraulic lockout share the same switch on the machine. See illustration 8. Depress the bottom of the switch in order to activate the interlock override. (IT IS ACTIVATED PER THE LIGHT BEING ON, IT WILL NOT TURN OFF) The switch tells the ECM that the operator wants to be able to raise the armrest in order to exit the seat while the continuous flow function is active. (VERIFIED CONTINUOUS FUNCTION DOES INDEED WORK, BOTH DIRECTIONS, HOWEVER IT DOES NOT WORK WITH THE ARMREST RAISED) The switch is a momentary, normally open rocker switch (VERIFIED). Pressing the switch puts a ground on the pin 64 of the ECM. (PIN 64 IS THE PINK WIRE AT THE SWITCH, IT DOES NOT HAVE CONTINUITY TO GROUND UNLESS THE MOMENTARY SWITCH IS PRESSED, SO IT SHOULD BE GOOD TO THE ECM?) The auxiliary hydraulic ECM monitors the status of the switch. If the input is grounded for 30 seconds or more, the ECM will interpret the signal as a stuck switch and the ECM will produce a diagnostic code.[/QUOTE] (I HELD THE SWITCH DOWN WITH WHILE CONFIRMING THERE WAS CONTINUITY FOR GROUND FOR 30 SECONDS AND NO CHANGE) Switch functions as it should, no shorts to ground.
The only test I can suggest is as follows: - 1. Remove the connector of the Auxiliary Control ECM. Identify Pin 64 (wire G982 PK). 2. Locate and disconnect wire 203 Black at the cab ground connection. That is the wire connecting the Interlock Override side of the switch to ground. It's one of five black wires at the cab ground stud. 3. With the Interlock Override switch in the centre position check for continuity between Pin 64 of the Aux ECM connector and the terminal of 203 Black at the cab ground connector. It should be open circuit. (Also try pressing the top side of the switch to engage the Implement Lockout just to see if the switch is playing silly buggers internally) 4. Press and hold the Interlock Override (bottom half) switch. Do you have continuity.? Does continuity come and go as you press & release the switch.? 5. Carefully remove wire G982 PK from the Aux Ctrl ECM connector. This will require a couple of something slim such as a fine watchmaker's screwdriver to raise the two plastic latches inside the big DRC connector and allow the wire to be removed. (There is also a tool for this, see the video @ 2:10) Refit the connector to the ECM. Power up the machine. Is the Interlock Override light still on.? If it is I suspect that you have a bad ECM because by removing wire G982 you have taken away the signal for the Interlock Override.
3. With the Interlock Override switch in the centre position check for continuity between Pin 64 of the Aux ECM connector and the terminal of 203 Black at the cab ground connector. It should be open circuit. (Also try pressing the top side of the switch to engage the Implement Lockout just to see if the switch is playing silly buggers internally) IT'S OPEN, NO FUNNY BUSINESS WITH SWITCH 4. Press and hold the Interlock Override (bottom half) switch. Do you have continuity.? Does continuity come and go as you press & release the switch.? YES, WORKS AS SHOULD, OPEN AND CLOSES BASED ON PRESSING AND RELEASING SWITCH 5. Carefully remove wire G982 PK from the Aux Ctrl ECM connector. This will require a couple of something slim such as a fine watchmaker's screwdriver to raise the two plastic latches inside the big DRC connector and allow the wire to be removed. (There is also a tool for this, see the video @ 2:10) Refit the connector to the ECM. Power up the machine. Is the Interlock Override light still on.? If it is I suspect that you have a bad ECM because by removing wire G982 you have taken away the signal for the Interlock Override. I LEFT GROUND WIRE 203 UNHOOKED, WOULD THIS ESSENTIALLY DO THE SAME THING? WITH 203 REMOVED THE LIGHT REMAINS ON.
Not necessarily. If there is some sort of hocus-pocus going on in the wiring harness anywhere between the Interlock Override switch (because you know that works) and the G982-PK wire terminal in Pin 64 of the Aux Ctrl ECM connector then it could potentially affect the test results. The only sure way I feel is to get the G982 wire connector out of the DRC connector. As an example there could be something hokey going on inside the DRC connector itself. It's a last throw of the dice but if it saves you buying a replacement ECM it's worth the effort IMHO. Get hold of a proper Deutsch tool if you have to, they are only about $2 each. Just make sure you get the right one for the SWG of the wire. In the case of G982 that is 18 SWG. https://theelectricaldepot.com/deut...-tools?zenid=5c5d8603ea6e15a6796475c28dc90436
5. Carefully remove wire G982 PK from the Aux Ctrl ECM connector. This will require a couple of something slim such as a fine watchmaker's screwdriver to raise the two plastic latches inside the big DRC connector and allow the wire to be removed. (There is also a tool for this, see the video @ 2:10) Refit the connector to the ECM. Power up the machine. Is the Interlock Override light still on.? If it is I suspect that you have a bad ECM because by removing wire G982 you have taken away the signal for the Interlock Override. LIGHT REMAINS ON Thinking back, this light used to flicker, sometime not come on. This was before I had the manual and I thought it was a restricted air filter warning. Not sure if that helps, but the light at one point was not illuminated constantly, which it is now. Do I need an ECM? That is not awesome.
If you completely removed the G982-PK wire socket from the DRC connector then you took away the method used to signal to the Aux Ctrl ECM that the Interlock Override switch is pressed. See the abridged ECM connection diagram below. Basically if machine frame ground is detected at Pin 64 then voltage to light the Interlock Override Lamp comes from Pin 18. the only other thing I can suggest is to investigate if somehow an extraneous voltage is getting to the Interlock Override Lamp from somewhere else in the warning lamp panel or elsewhere. So you'd have to trace wire M901-YL and check for continuity, etc. If the light is still on after doing that then I am pretty certain that there must be a problem inside the ECM. This is not unusual bearing in mind that condition of the ECM as shown by the "before" photos in your post further up. ECM's are somewhat waterproof but not 100%. I would say that your ECM probably has experienced some level of water ingress.
With M901-YL removed from ECM connector the light turns off, back probing the pin at the ECM there is a constant 8.5 volts at pin 18, this is all with G982-PK removed from pin 64. Any resources on having the ECM serviced? Any resources on where to purchase a used one? As it stands the light is on, and I can not activate the hydraulic interlock override. Any other concerns? Thank you for all the help Nige!
The Part Number is 216-0658 or Reman 10R-5613, that's all I know. There are places that repair ECMs but I don't have any recommendations as to where. So long as you know that the Interlock Override could be on or off despite the light being permanently on I can't think of anything.
I assembled everything back to stock and tested the aux hydraulics with nothing attached and it seemed to work. Went to use the auger today and no Aux hydraulics at all. Beginning to lose my patience. It worked fine until I started wondering why this light was on.
Got back to it, aux hydraulics were inop so I traced out and decided the ECM was their likely culprit as well. They came back once, then went out again while testing with wildly different results so I split the ECM open and its toast. Full of water and there is rust all over the circuit board.
Not good news but at least it confirms what we suspected a while back after all the testing.
Before and after some time in the ultrasonic cleaner, a toothbrush, and baking soda. Everything seems to work properly now, only time will tell. Pulled the main ECM and split it open, it is in better shape but also has signs of water intrusion. Will seal them both and cross my fingers!!
Yeah, Cat really didn’t think it through very well when they decided to locate the ECMs in the basement. Either that or they failed to pay enough attention to waterproofing them, or a combination of both.
The output voltage to the A1/A2 solenoids changed as the aux controls came and went but they were definitely both energized from the ECM randomly. Also, I had high resistance across the signal and return wire to the joystick pins 52/53 per the below info I found. Hoping that high resistance was just the buildup in the ECM, and not the cracked wheel in my first post... I will double check when reassembled. Helpful: Test Step 4. CHECK THE OUTPUT OF THE ECM Remove the floorplate in order to get to the ECM. Locate the wires P978-GN and L998-OR coming out of the ECM. Enable the machine. Push down on the A1 switch. Measure the voltage from wire P978-GN to wire L998-OR. Measure the voltage on the back side of a connector or by penetrating the wire insulation. ( A 1/16" DRILL BIT SLIPS RIGHT INTO THE ECM CONNECTOR TO BACK PROBE WITHOUT DAMAGING ANYTHING) Note: Two people will be needed to perform the measurements. One person will need to occupy the seat in order to keep the machine enabled. The other person will take the measurement. Expected Result: The voltage should be greater than 10 VDC. Results: OK - The voltage is greater than 10 VDC. Repair: The problem does not appear to be electrical. NOT OK - The voltage is less than 10 VDC. Repair: The ECM is very unlikely to have failed. Reconnect all connections and visually inspect the wire harness. Verify that the values that are present on the machine configuration screen match the machine's options. Verify that the values that are present on the machine configuration screen are installed correctly. Verify that the diagnostic code still exists. If the diagnostic code still exists perform the test steps again.Replace the ECM, if the cause of the diagnostic code was not found after the second attempt. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace". Test Step 5. CHECK THE SWITCH CIRCUIT Remove the floorplate in order to get to the ECM. Remove the wire harness from the ECM. Press the switch (A1) Measure the resistance from contact 52 to contact 62 of the wire harness connector. Press the switch (A2). Measure the resistance from contact 52 to contact 53 of the wire harness connector. Expected Result: The resistances should be less than 5 Ohms on both of the readings. Results: OK - The resistances were less than 5 Ohms. Repair: The ECM is very unlikely to have failed. Reconnect all connections and visually inspect the wire harness. Verify that the values that are present on the machine configuration screen match the machine's options. Verify that the values that are present on the machine configuration screen are installed correctly. Verify that the diagnostic code still exists. If the diagnostic code still exists perform the test steps again.Replace the ECM, if the cause of the diagnostic code was not found after the second attempt. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace". NOT OK - The resistances were greater than 5 Ohms. Repair: The circuit is open in the wire harness and/or the connector. Repair the wire harness and/or the connector or replace the wire harness and/or the connector.
Hello, when you put this in the cleaner, did you place the whole thing in as shown here or did you completely remove the circuit board from the case?
The board is glued into the case, I submerged the whole thing. It worked for awhile but all of the symptoms returned, pulling the ECM shows the damage of course remains. I need to replace the ECM completely.
Okay thanks for clarifying. I appreciate it.