P0601

DESCRIPTION
The Powertrain Control Module (PCM) has detected a failure in the communication circuitry.

CONDITION FOR RUNNING THE DTC
The ignition is ON.

CONDITIONS FOR SETTING THE DTC
An error was detected in the EEPROM data readout.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM illuminates the Malfunction Indicator Lamp (MIL).
^ The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame buffer.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The MIL turns OFF after 3 consecutively passing trips without a fault present.
^ A history DTC clears after 40 consecutive warm-up cycles without a fault.
^ Perform the scan tool Clear DTC Information function.

DIAGNOSTIC AIDS
Check the PCM for water contamination. Water entering the PCM can cause damage and corrosion to the circuit boards and to internal components. Repair the source of the water entry before the installation of a replacement PCM.

A DTC P0601 can set if an incorrect PCM is installed in the vehicle. Install the correct PCM according to the vehicle and/or the engine type and equipment options.

TEST DESCRIPTION

Steps 1-5:

The numbers below refer to the step numbers in the diagnostic table.
1. The Diagnostic System Check-Computers and Control Systems prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
2. This step determines if the fault is present. Replace the PCM if this DTC sets again.