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For 1990-2009 cars only

Powertrain Control Module Replacement/Programming Repair Procedure

Notice: In order to prevent possible electrostatic discharge damage to the PCM, do not touch the connector pins or 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 PCM Replacement, check the PCM first to see if it is the correct part. If the PCM is faulty, remove it and install the new service PCM.

The new service PCM will not be programmed. You must program the new PCM. DTC P0602 indicates the EEPROM is not programmed or has malfunctioned.

Notice: In order to prevent possible electrostatic discharge damage to the PCM, do not touch the connector pins or soldered components on the circuit board.

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 (controller), 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.

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.

Removal Procedure

  1. Disconnect the negative battery cable.
  2. Remove the coolant reservoir.
  3. Remove the SMCC module from the SMCC module bracket.
  4. Remove the SMCC module bracket.
  5. Remove the left front strut brace.
  6. Remove the PCM cover from the air cleaner housing.
  7. Remove the PCM from the air cleaner housing.
  8. If the PCM is being replaced, remove the KS module for installation in the new PCM.

Installation Procedure

  1. If a new PCM is being installed, install the KS module from the original PCM.
  2. Install the PCM into the air cleaner housing.
  3. Install the PCM cover to the air cleaner housing.
  4. Install the left front strut brace.
  5. Install the SMCC module bracket.
  6. Install the SMCC module to the SMCC module bracket.
  7. Install the coolant reservoir.
  8. Be sure to check coolant system for proper level. Refer to Cooling System.

  9. Install the negative battery cable.
  10. If a new PCM is being installed, program the EEPROM.
  11. The PCM will need to learn the crankshaft variation. Refer to Powertrain Control Module Replacement/Programming

EEPROM Programming

  1. Set-up - Ensure that the following conditions have been met:
  2. • The battery is fully charged and battery charger is not connected.
    • The ignition is on.
    • The Techline equipment cable connection at the DLC is secure.
  3. Program the PCM using the latest software matching the vehicle. Refer to up-to-date Techline equipment users instructions.
  4. If the PCM fails to program, proceed as follows:
  5. •  Ensure that all PCM connections are OK.
    •  Check the Techline equipment for the latest software version.
    •  Attempt to program the PCM. If the PCM still cannot be programmed properly, replace the PCM. You must program the replacement PCM.

Functional Check

  1. Clear DTCs.
  2. Perform the Powertrain On Board Diagnostic (OBD) System Check .
  3. Start the engine and the engine run for one minute.
  4. Use the scan tool in order to scan for the DTCs.
  5. If DTC P0325 sets, the KS module is not fully seated, is missing, or is malfunctioning.

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.

Caution: Before performing the Crankshaft Position System Variation Learning Procedure always set the vehicle parking brake and block the drive wheels in order to prevent personal injury. Release the throttle immediately when the engine starts to decelerate in order to eliminate over revving the engine. Once the learn procedure is completed, the control module will return engine control to the operator and the engine will respond to the throttle position.

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 24X 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 24X crank signal, refer to DTC P0336 Crankshaft Position (CKP) Sensor Performance .
The scan tool crankshaft position system variation learn function will not be enabled until engine coolant temperature is greater than 70° C (158° F).

Selecting the crankshaft position variation learn procedure on the scan tool will command the PCM to enable CKP system variation learn cut-off and allow the crankshaft position system compensating values to be stores in the PCM. The PCM must be detect an engine speed of 5150 rpm (CKP system variation learn fuel cutoff) during the crankshaft position system variation learn procedure to store the crankshaft position system compensating values and complete the procedure.

  1. Set the parking brake.
  2. Block the drive wheels.
  3. Ensure the hood is closed.
  4. Start the engine and allow engine coolant temperature to reach at least 70°C (158°F).
  5. Turn OFF the ignition switch.
  6. Select and enable the crankshaft position variation learn procedure with the scan tool
  7. Start the engine.
  8. Apply and hold the service brake pedal firmly.
  9. Ensure the transaxle is in park.
  10. Increase accelerator pedal position until ckp system variation learn fuel cutoff is reached. CKP system variation learn fuel cutoff is reached at 5150 rpm. Immediately release the accelerator pedal when fuel cutoff is reached.
  11. The crankshaft position system variation compensating values are learned when the rpm decreases back to idle.
  12. Observe DTC status for DTC P1336.
  13. 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.