P0976 question

Tuner923

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Is definetly do one of the above before dropping $50 on a BCM.

All Data is a digital database technicians use, basically every service manual for every car accessed on computer... also allows access to TSBs and recalls ect..

Terry,

I have looked up the DTC P0976 and found that it is triggered when the TCM detects a short to ground. The reading of 1.3v I am assuming that was a -1.3v meaning a short to ground. You indicated that you found the wiring harness to be rubbing on the bell housing and after having fixed this it solved the voltage reading on the load side of the fuse. From here have you cleared the code? if yes has it reappeared? If it has reappeared I would start diagnosis on the solenoid to see if it have an internal short to ground.
 
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YelloEye

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All Data is a digital database technicians use, basically every service manual for every car accessed on computer... also allows access to TSBs and recalls ect..

Nice, I wish I could access that from home. I can only access it at the library.
 

skynyrdcat

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All Data is a digital database technicians use, basically every service manual for every car accessed on computer... also allows access to TSBs and recalls ect..

Terry,

I have looked up the DTC P0976 and found that it is triggered when the TCM detects a short to ground. The reading of 1.3v I am assuming that was a -1.3v meaning a short to ground. You indicated that you found the wiring harness to be rubbing on the bell housing and after having fixed this it solved the voltage reading on the load side of the fuse. From here have you cleared the code? if yes has it reappeared? If it has reappeared I would start diagnosis on the solenoid to see if it have an internal short to ground.

Yes and no. Actually, I was reading the diagram wrong (the all data tcm diagram is backwards to how it actually lines up in the vehicle). Fortunately the plug has the 1 and 37 wires labeled so I was able to work backward from there. I originally thought the TCM sent power to the solenoids and commanded a ground via the the trans case. However the power goes straight from the fuse block, thru the solenoids and back to the TCM. The TCM then commands a ground inside the TCM.
Disregarding everything mentioned in earlier posts...
The problem turned out to be the ign wire going into the trans. When I unplugged the harness from the trans housing, the male terminal on the trans side was still inside the female terminal on the engine side, and it was slightly black around it. This is the wire that give ign voltage to the 1-2, 3-4 and TCC (I got the TCC P2764 code too).

THE MORAL OF THE STORY... Don't use a test light/ meter to test voltage by probing the insulation on the back side of the connector. Unplug it and make sure you have power to the terminal end!!!!!!

I still haven't repaired it yet, I've got to figure out how to the the trans side connector out. It looks like the connector releases to the inside, so I'll probably be taking the side pan off.

For future reference, if you get a p0976, check for power to the trans fuse in the block, check the fuse itself and if those are good check the number 2 and number 20 wires on the TCM for ignition voltage. If it's not there, the circuit is open somewhere between the trans fuse to solenoid and the solenoid to TCM wiring.
Same thing for the p2764 except it will be the #1 wire on the TCM connector.

Now to figure out if i've got to pull the side cover :think:
 

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