pistolpete817

The check engine light came on after I connected a Cen-Tec (Harbor Freight) code scanner. The scanner shows a pending P0700 DTC and a historic P0700. This appears to to be a communication code for the TCM (Transmission Control Module). The manual says it can only be reset by clearing the TCM emission error code. I can't find the path to clear the TCM code.

The transmission (2009 A6) seems to run and shift correctly in Drive and Sport.

Any suggestions on clearing the code?
What problem would cause a valid code?

RicK T

Well we just recently learned that the P0700 doesn't mean anything. It is just the code saying that the trans failed a diagnostic. There has to be another code associated with the condition that caused the diagnostic failure. Anyway, here is that recent thread. It is interesting but you will likely be most interested in posts 16, 22 and 24. Best of luck and let us know what happens:

http://forums.corvetteforum.com/c6-c...nsmission.html

pistolpete817

Thanks for the reply. That thread answered a lot. It looks like this has been a problem before. The car only has 2800 miles so it should be covered by the dealer.


Thanks

Gene Culley

I love Harbor Freight, lol. How much did it cost may I ask?

DTC P0700
Diagnostic Instructions
• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor
DTC P0700: Transmission Control Module (TCM) Requested MIL Illumination

Circuit/System Description
The transmission control module (TCM) uses the (GMLAN) to signal the engine control module (ECM) that the TCM is requesting malfunction indicator lamp (MIL) illumination. This happens when the TCM has determined that a failure affecting emissions has occurred in transmission control system. When the ECM receives the a message from the TCM, DTC P0700 will set.

Conditions for Running the DTC
The ignition is ON.

Conditions for Setting the DTC
The TCM is requesting MIL illumination.

Action Taken When the DTC Sets
DTC P0700 is a Type A DTC.