P0601

CIRCUIT DESCRIPTION
The PCM used in this vehicle utilizes an Electrically Erasable Programmable Read-Only Memory (EEPROM). The EEPROM contains program information and the calibrations required for powertrain diagnostics operation.

Unlike the PROM used in past applications, the EEPROM is not replaceable. When the PCM is replaced or a calibration update is required, the PCM must be programmed using approved Techline equipment.

CONDITIONS FOR RUNNING THE DTC
The ignition is in the crank or run position.

CONDITIONS FOR SETTING THE DTC
The PCM does not contain the correct program required to operate the vehicle.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the first trip in which the diagnostic test has been run and failed.
^ The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

DIAGNOSTIC AIDS
DTC P0601 indicates that the contents of the EEPROM have changed since the PCM was programmed. The only possible repair is PCM replacement. Remember to program the replacement PCM with the correct software and calibration for the vehicle.

TEST DESCRIPTION

Diagnostic Chart:

The numbers below refer to the step numbers on the diagnostic table.
2. This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.