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For 1990-2009 cars only

Powertrain Control Module (PCM)


Object Number: 61240  Size: SH

The Powertrain Control Module (PCM), located under the instrument panel, is the control center of the fuel injection system. It constantly looks at the information from various sensors, and controls the systems that affect emission or engine performance. The PCM also performs the diagnostic function of the system. It can recognize operational problems, alert the driver through the Malfunction Indicator Lamp (MIL), and store a DTC or DTCs which identify the problem areas to aid the technician in making repairs.

Removal Procedure

    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.

  1. Disconnect the negative battery cable.
  2. Remove the LH hush panel.

  3. Object Number: 72295  Size: SH
  4. Loosen the PCM connector screws (1).

  5. Object Number: 102470  Size: SH

    Notice: Do not touch the PCM connector pins or soldered components on the circuit board in order to prevent possible electrostatic discharge (ESD) damage. Do not remove the integrated circuit boards from the carrier.

  6. Disconnect the PCM electrical connectors.

  7. Object Number: 72298  Size: SH
  8. Remove the PCM Retainer.
  9. Slide the PCM from the PCM bracket.

Installation Procedure

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.

  1. Slide the PCM into the PCM bracket.
  2. Install the PCM Retainer.
  3. Notice: Do not touch the PCM connector pins or soldered components on the circuit board in order to prevent possible electrostatic discharge (ESD) damage. Do not remove the integrated circuit boards from the carrier.


    Object Number: 102470  Size: SH
  4. Install the PCM electrical connectors.
  5. 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.

  6. Tighten the PCM connector screws (1).
  7. Reinstall the LH hush panel.
  8. 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.

  9. Connect the negative battery cable.
  10. Program the EEPROM.
  11. Important :  Replacement PCMs must be reprogrammed and the crankshaft position system variation learn procedure must be performed.

  12. The PCM will need to relearn the crankshaft variation. Refer to Crankshaft Position System Variation Learn .

EEPROM Programming


    Object Number: 72295  Size: SH
  1. Set-up -- Ensure that the following conditions have been met:
  2. • The battery is fully charged and a battery charger is disconnected.
    • 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. Perform the Powertrain On Board Diagnostic (OBD) System Check .
  2. Start the engine and the engine run for one minute.
  3. Use the scan tool in order to scan for the DTCs.