Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Did it get stuck in 4 lo when it was very cold outside?
What codes if any are being stored by the TCCM or Transfer Case Control Module?
It's cheaper to have someone scan it than to go buy a scanner that can communicate with that system.
Most generic scanners can get engine and trans trouble codes that are setting currently. Some don't even display codes that are set in history even though they are in the computer.
As far as the cold temp, I was talking more like -10 F or so. We had a lot of vehicles stuck in 4 lo this last winter. By the time they came into the shop and got thawed out, everything started working again.
I do know that if you look in your history repairs from the dealer, they should have documented which code or codes were setting. Maybe that will give us a clue.
I would think they should at least scan the computer for you. If you wind up with something like a C0327 and they replaced the encoder motor sensor but failed to reprogram the TCCM then the new sensor may have failed again. The factory has several updates for TCCM calibration errors so they need to be updated if they weren't.
There are also documents from the factory that talk about delays or hard time coming out of 4 hi or 4 lo if you have badly worn or mismatched tires. The tire size mismatch causes severe binding in the transfercase and won't allow the gears and clutches to uncouple. Make sure your tires are matched closely as far as their total circumference.
If you have new tires on the back and worn tires on the front and it goes intoXXXXX then the different size tires spin at different speeds which is where the binding occurs.
Let me know if you find any documentation. Maybe try hooking things back up again and give it a try.
Okay I have the receipts from the prior dealer visits. The first time they listed the SOP special ordered part 845cpdrb and they also list 31985 SOP encoder motor. the four wheel worked for a while. we would put it in 4wheel from time to time as suggested. the second time there is a note stating the cause: shorted, they list K4124 sensor assembly, transfer case range, selector replace, 750WCDRO XXXXXXXXX sensor, FC: 6g, part #: 88962315. Again the invoice notes the "24424 encoder motor sensor shorted wcdro replace encoder motor sensor". Again the 4wheel worked for a while. The third time, "cause: shorted. k4126 gasket, transaxle case to housing replace, 508wcdro. 1 88962314 actuator, fc: 6g, Part#: 88962314". It further stated, "33551 found code c0327 following diag sheet doc#(NNN) NNN-NNNNled me to step 13 to replace encoder motor replaced encoder motor cleard code". Once again the 4wheel worked for quite a while then one evening it on its own shifted into 4wheel low and would not shift out. we disconnected the wire/plug to disengage it and have been driving it in 2wheel ever since. The dealer now won't touch it unless we pay. All these codes are greek to me, but perhaps you can gleam something from it. Thank you for your help, Matt
The code C0327 is a problem with the encoder motor sensor. This is the sensor that tells the transfercase module or controller which gear the transfercase is really in. If they keep replacing the encoder sensor but NEVER reprogrammed the controller with the latest update for repeat sensor failure, then that's why the sensor keeps failing. I won't go into specifics about what the reprogramming does as I don't wan't to confuse you, but let's just say that the new calibration prevents premature sensor failure.
If they never reprogrammed it, they're responsible, plain and simple.
Remind them of Bulletin PIP3840M and have them at least make sure they have your module updated.
Hope this gets things squared away for you.