Loss of DTC Memory

WARNING: This page is about a different car, the 2003 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.

To check for proper DTC Memory function, perform the following procedure:

Observe the conditions for running the DTC for the Throttle Position (TP) sensor circuit low voltage DTC.
Disconnect TP sensor 3-pin harness connector.
Operate vehicle within Conditions for Running the DTC.
MIL should illuminate upon completion of all the Conditions for Running the DTC. Two key cycles or drive trips may be required.
A TP sensor circuit low voltage DTC should be stored in the PCM and remain in memory when the ignition is turned OFF.

A failure to store a DTC or failure of the DTC to remain in memory may indicate a faulty PCM.