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For 1990-2009 cars only

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: Begin the crankshaft position system variation learn procedure with the ignition switch OFF. Do not turn ON the ignition switch or start the vehicle unless instructed to do so by the scan tool.

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. Clear DTCs before attempting to perform the crankshaft position system variation learn procedure. If any DTCs reset, the DTCs must be diagnosed and repaired before the crankshaft position system variation learn procedure can be successfully completed.

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 that a problem with the camshaft position signal exists, refer to DTC P0341 Camshaft Position (CMP) Sensor Performance .
   • If the scan tool indicates that a problem with the 3X crank signal exists, refer to DTC P1374 Crankshaft Position (CKP) High to Low Resolution Frequency Correlation .
   • If the scan tool indicates that a problem with the 18X crank signal exists, refer to DTC P0336 Crankshaft Position (CKP) Sensor Circuit .
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 system variation learn procedure on the scan tool will command the PCM to enable CKP system variation learn fuel cutoff and allow the crankshaft position system variation compensating values to be stored in the PCM. The PCM must 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 variation compensating values and complete the procedure.

  1. Set the parking brake.
  2. Block the drive wheels.
  3. Ensure that 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 vehicle
  8. Apply and hold the service brake pedal firmly.
  9. Ensure that 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 RPM decreases back to idle. If the procedure terminates, refer to Important above for instructions.
  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.

Powertrain Control Module Replacement/Programming PCM Replacement/Reprogramming

Service of the PCM normally consists of PCM replacement or PCM reprogramming. If the diagnostic procedures call for PCM replacement, check the PCM first to see if it is the correct part. If the PCM is malfunctioning, 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 that the PCM 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.

Removal Procedure

    Important: It is necessary to record the remaining engine oil life. If the replacement module is not programed with the remaining engine oil life, the engine oil life will default to 100%. If the replacement module is not programmed with the remaining engine oil life, the engine oil will need to be changed at 5000 km (3,000 mi) from the last engine oil change.

  1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.
  2. Disconnect the negative battery cable.

  3. Object Number: 156011  Size: SH
  4. Remove the PCM cover shield .

  5. Object Number: 156018  Size: SH
  6. Remove the PCM from the mounting bracket.
  7. Disconnect the harness connectors from the PCM.
  8. Remove the PCM from the engine compartment.
  9. If the PCM is being replaced, remove the KS module for installation in the new PCM. Go to Knock Sensor Module Replacement .

Installation Procedure


    Object Number: 156018  Size: SH
  1. If a new PCM is being installed, install the KS module from the original PCM. Go to Knock Sensor Module Replacement .
  2. Connect the harness connectors to the PCM.
  3. Install the PCM into the mounting bracket.

  4. Object Number: 156011  Size: SH
  5. Install the PCM cover.
  6. Connect the negative battery cable.
  7. If a new PCM is being installed, program the PCM.
  8. Perform the crankshaft position system variation learn procedure. Refer to Powertrain Control Module Replacement/Programming .

PCM Programming

  1. Set-up - Ensure that the following conditions have been met:
  2. • The battery is fully charged.
    • 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 user's 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 On-Board Diagnostic System Check.
  3. Start the engine and run for one minute.
  4. Use the scan tool to check for DTCs.
  5. If DTC P0325 is set, the KS module is not fully seated, is missing, or is malfunctioning.
  6. If DTC P1336 is set, perform the crankshaft position system variation learn procedure. Refer to Powertrain Control Module Replacement/Programming .