The powertrain control module (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 programmable read only memory (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.
Tested continuously during crank or running
The PCM detects a problem with internal programming.
• | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
• | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records. |
• | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
• | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
• | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
• | Clear the MIL and the DTC with a scan tool. |
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.
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Yes | No |
---|---|---|---|
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |
Replace the PCM. Refer to Powertrain Control Module Replacement . Is the action complete? | Go to Step 3 | -- | |
3 |
Does the DTC run and pass? | Go to Step 4 | Go to Step 2 |
4 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | System OK |