Diagnostic Aids

If DTC P0463 and DTC P1639 are set in the PCM, Diagnose DTC P1639 first.

Use the Freeze Frame and/or Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame/Failure Records data may help in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also help in determining the number of ignition cycles that the diagnostic test reported a pass and/or fail. Operate the vehicle within the same freeze frame conditions including those for RPM, for engine load, for vehicle speed, for temperature, and for others. This will isolate at what point the DTC failed.

Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS  in Wiring Systems.