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For 1990-2009 cars only

Powertrain Control Module (PCM)

Notice: In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or reconnecting the PCM connector.

Service of the PCM should normally consist of either replacement of the PCM, EEPROM re-programming or a KS module change.

If the diagnostic procedures call for the PCM to be replaced, the PCM should be checked first to see if it is the correct part. If it is, remove the KS module from the faulty PCM and install it in the new service PCM. The service PCM will not contain a KS module. DTC P0601 indicates the EEPROM programming has malfunctioned. When DTC P0601 is obtained, re-program the EEPROM. If a DTC P0325 is set, check the KS module for proper installation. If it is installed correctly and DTC P0325 is still displayed, replace the KS module.

The ignition should be OFF for at least 10 seconds before disconnecting power to the PCM so the IAC valve has time to move to the engine OFF position.

Removal Procedure


    Object Number: 12965  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 RH engine splash shield.
  4. Remove the horn attaching bolt.
  5. Disconnect the horn electrical connector and horn.
  6. Remove the PCM retainer attaching bolts.
  7. Slide the PCM (4) and retainer from PCM bracket (2).
  8. Disconnect the PCM electrical connectors (3).
  9. Remove the retainer from PCM.

  10. Object Number: 10782  Size: SH

    Important: Before removing KS module cover, carefully clean PCM housing of any debris that may cause damage to PCM circuitry.

  11. Remove the KS module cover.

  12. Object Number: 10783  Size: SH

    Important: To prevent possible Electrostatic Discharge damage to the PCM or KS module, DO NOT touch the connector pins or soldered components on the circuit board and DO NOT remove the integrated circuit boards from the carrier.

  13. Remove the KS module.

Removal Procedure

  1. Remove the new PCM from its packaging and check the service number to make sure it is the same number or updated number as the faulty PCM.

  2. Object Number: 10782  Size: SH
  3. Remove the KS module cover.

Installation Procedure

Important: Refer to the Latest Techline Information on Re-Programming or Flashing procedures.


    Object Number: 10783  Size: SH
  1. Install the KS module in KS module socket.

  2. Object Number: 10781  Size: SH
  3. Install the KS module cover.
  4. Tighten
    Tighten the KS module cover screws to 2.8-3.2 N·m (25-28 lb in).

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  5. Slide the PCM (4) into PCM retainer.
  6. Connect the PCM electrical connectors (3).
  7. Slide the PCM retainer into PCM bracket (2) slots.
  8. Install the PCM retainer attaching bolts.
  9. Tighten
    Tighten the PCM retainer attaching bolts to 8-12 N·m (6-9 lb ft).

  10. Connect the horn electrical connector and horn.
  11. Install the horn attaching bolt.
  12. Install the RH engine splash shield.
  13. Connect the negative battery cable.