Diagnostic Aids
WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
DTCs P1AEC and P1AED compare the MCM measured high voltage to the BECM measurement of high voltage which is broadcast over GMLAN. Conditions that cause the BECM to improperly measure high voltage or a failure of the BECM to transmit its high voltage value may set this DTC.
DTCs P1AEE and P1AEF indicate that the high voltage contactor relays may have opened while large current flow was present. Conditions such as loss of BECM power or ground or removal of the high voltage manual disconnect while the vehicle was driving create a voltage surge that may set this DTC.