I have an 850C Dozer serial TO850CX932110 that has a dead left track. I verified that the manual overrides will not make the left side move. I'm digging into that further next week. Thinking of switching the front pump multi Function valves with the rear to see if the dead track moves to the right...Someone previously changed some parts like PCP valves and the speed sensor on the left motor. I have 2 hard codes F437 and F465. do I need to resolve those codes before it will let me calibrate ? I can't seem to get it to calibrate the ECU and TCU
Welcome to HEF CantonMike ! Those are the only codes? Until you have movement of the left track, calibration will never happen. It does not move in either direction? Was charge pressure checked? Charge pressure while trying to move track? Charge pressure to the servo when moving the little lever? Do you have the manual TM1588? It has some good diagnostic flow charts. The F437 Temp sensor code will not affect calibration. The F465 Throttle calibration code needs to be repaired before the TCU will calibrate. Start with a physical throttle position sensor adjustment.
Update- I replaced the plug for the fuel temp sensor so now I no longer have any stored or active codes. (the code F465 is no longer active either) I still can't calibrate the ECU. I get to the screen that says ECU Calibration but it does not seem to do anything. I pushed select but nothing changes....That's one problem. As for the dead left track, I swapped the upper multi function valves from the front pump to the back and the problem is the same. I replaced the transmission pressure gauge on the dash and have good pressure initially but then at 1800 rpm when i lower the park brake lever the pressure drops by 20 lbs then rebounds. My next thought its to rebuild the park brake valve...suggested by the manual...your thoughts? Is the dash gauge sufficient to do charge pressure assessment ?
How are you performing the procedure? Starting the engine or just keying on. Calibrating the ECU is different from the calibrating the TCU. Are you following the procedure in the manual to the letter? For your dead track, are you following the "One Track Does Not Move" flow chart? I would also concentrate on getting any calibrations done first. The momentary drop is normal. What specific pressure are you reading? I prefer plugging physical gauges into the machine. No, do not reseal the park brake valve. If that was your issue, you would have trouble with both tracks.