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For 1990-2009 cars only

Powertrain Control Module Replacement/Programming Replacement

Notice: In order to prevent possible Electrostatic Discharge damage to the PCM, Do Not touch the connector pins or the soldered components on the circuit board.

Service of the PCM should normally consist of either replacement of the PCM or EEPROM programming. If the diagnostic procedures call for the PCM to be replaced, PCM should be checked first to see if it is the correct part. If it is, remove the faulty PCM and install the new service PCM.

Notice: Turn the ignition OFF when installing or removing the PCM connectors and disconnecting or reconnecting the power to the PCM (battery cable, PCM pigtail, PCM fuse, jumper cables, etc.) in order to prevent internal PCM damage.

Important: When replacing the production PCM with a service PCM, it is important to transfer the broadcast code and production PCM number to the service PCM label. Do not record on PCM cover. This will allow positive identification of PCM parts throughout the service life of the vehicle.

THE SERVICE PCM EEPROM WILL NOT BE PROGRAMMED. DTC P0602 indicates the EEPROM is not programmed or has malfunctioned.

Removal Procedure


    Object Number: 15949  Size: SH
  1. Disconnect the negative battery cable.
  2. Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  3. Remove the right hand sound insulator.
  4. Remove the PCM.
  5. Remove the PCM connectors.
  6. Remove the PCM access cover.
  7. Remove the Knock Sensor (KS) module. Refer to Knock Sensor.

Installation Procedure


    Object Number: 15949  Size: SH
  1. If a new PCM is being installed, install the KS module from the original PCM. Refer to Knock Sensor Module.
  2. Install the access cover on PCM.
  3. Install the connectors to PCM.
  4. Install the PCM.
  5. Install the right hand sound insulator.
  6. Connect the negative battery cable.

If a new PCM is being installed, program the EEPROM.

After the EEPROM is programmed the PCM will need to relearn the CKP Variation. Refer to Powertrain Control Module Replacement/Programming .

EEPROM Programming

  1. Set-up - Ensure that the following conditions have been met:
  2. • The ignition is ON.
    • The Techline equipment cable connection at the Data Link Connector (DLC) is secure.
    • The vehicle battery is fully charged and a battery charger is not connected.
  3. If the PCM fails to program, check the Techline equipment for the latest software version.
  4. Attempt to program the PCM. If the PCM still cannot be programmed properly, replace the PCM. The replacement PCM must be programmed.

Functional Check

  1. Perform On-Board Diagnostic System Check.
  2. Start engine and run for one minute.
  3. Scan for DTCs using the scan tool.
  4. If DTC P0325 sets, the KS module is not fully seated, is missing, or is faulty.

Powertrain Control Module Replacement/Programming CKP Variation Learn Procedure

The crankshaft position system variation compensating values are stored in the PCM non-volatile memory after a learn procedure has been performed. If the actual crankshaft position system variation is not within the crankshaft position system variation compensating values stored in the PCM, DTC P0300 may set (refer to Diagnostic Aids for DTC P0300).

The Crankshaft Position System Variation Learn Procedure should be performed if any of the following conditions are true:

    • DTC P1336 is set.
    • The PCM has been replaced.
    • The engine has been replaced.
    • The crankshaft has been replaced.
    • The crankshaft harmonic balancer has been replaced.
    • The crankshaft position sensor has been replaced.

Important: The scan tool crankshaft position system variation learn function will be inhibited if engine coolant temperature is less than 70°C (158°F). Allow the engine to warm to at least 70°C (158°F) before attempting the crankshaft position system variation learn procedure.

The scan tool crankshaft position system variation learn function will be inhibited if any powertrain DTCs other than DTC P1336 are set before or during the crankshaft position system variation learn procedure. Diagnose and repair any DTCs if set.

The crankshaft position system variation learn function will be inhibited if the PCM detects a malfunction involving the camshaft position signal circuit, the 3X reference circuit, or the 18X reference circuit.

   •  If the scan tool indicates a problem with the Cam signal, refer to DTC P0341 Camshaft Position (CMP) Sensor Performance .
   • If the scan tool indicates a problem with the 3X crank signal, refer to DTC P1374 Crankshaft Position (CKP) High to Low Resolution Frequency Correlation .
   •  If the scan tool indicates a problem with the 18X crank signal, refer to DTC P0336 Crankshaft Position (CKP) Sensor Circuit .

  1. Set the parking brake.
  2. Start the engine and allow engine coolant temperature to reach at least 70°C (158°F).
  3. Turn OFF the ignition switch.
  4. Select the crankshaft position variation learn procedure from the scan tool special functions list.
  5. Follow the instructions displayed on the scan tool. If the procedure is terminated, refer to Important above for instructions.
  6. Observe DTC status for DTC P1336.
  7. If the scan tool indicates that DTC P1336 ran and passed, the crankshaft position system variation learn procedure is complete. If the scan tool indicates DTC P1336 failed or not run, check for other DTCs. If no DTCs other than P1336 are set, repeat the crankshaft position system variation learn procedure as necessary.

Powertrain Control Module Replacement/Programming Password Learn Procedure

The password learn procedure is a follows:

  1. Attempt to start the engine
  2. Leave the engine in the ON position.
  3. The theft system lamp will flash for 10 minutes.

  4. When the theft system lamp stops flashing, start the vehicle.
  5. Once the engine is running the pasword is succesfully learned.