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For 1990-2009 cars only

Powertrain Control Module Programming On-Board

Before Programming a Control Module

Important: Do NOT program a control module unless you are directed by a service procedure or you are directed by a General Motors Corporation service bulletin. Programming a control module at any other time will not permanently correct a customers concern.

Ensure the following conditions are met before programming a control module:

    • Vehicle system voltage
       - There is no charging system concern. All charging system concerns must be repaired before programming a control module.
       - Battery voltage is greater than 12 volts but less than 16 volts. The battery must be charged before programming the control module if the battery voltage is low.
       - A battery charger is NOT connected to the vehicle's battery. Incorrect system voltage or voltage fluctuations from a battery charger, may cause programming failure or control module damage.
       - Turn OFF or disable any system that may put a load on the vehicle's battery.
   • Twilight sentinel
   • Interior lights
   • Daytime running lights (DRL)--Applying the parking brake, on most vehicles, disables the DRL system. Refer to the Owners manual.
   • Heating, ventilation, and air conditioning (HVAC) systems
   • Engine cooling fans etc.
    • The ignition switch is in the proper position. The scan tool prompts you to turn ON the ignition, with the engine OFF. Do NOT change the position of the ignition switch during the programming procedure, unless instructed to do so.
    • All tool connections are secure.
       - RS-232
       - The connection at the data link connector (DLC) is secure.
       - Voltage supply circuits
    • DO NOT disturb the tool harnesses while programming. If an interruption occurs during the programming procedure, programming failure or control module damage may occur.

Remote Programming

  1. Turn OFF the ignition.
  2. Install the Tech 2 to the data link connector (DLC).
  3. Turn ON the ignition, with the engine OFF.
  4. Turn OFF all of the vehicle accessories.
  5. With the Tech 2, select Service Programming.
  6. Identify vehicle information as requested by the Tech 2.
  7. Select the type of module you are programming.
  8. Select the type of programming to be performed.
  9. Verify the displayed VIN with the vehicle VIN. If the displayed VIN does not match the actual VIN, write down the actual VIN and correct the VIN at the Techline terminal.
  10. When complete, Exit Service Programming.
  11. Turn OFF the Tech 2 and disconnect the Tech 2 from the vehicle.
  12. Turn OFF the ignition.
  13. Connect the Tech 2 to the Techline terminal.
  14. Select Service Programming.
  15. Select Tech 2 as the tool you are using.
  16. Select the type of programming to be performed.
  17. Verify the displayed VIN with the vehicle VIN. Correct the VIN as necessary.
  18. Select the type of module you are programming.
  19. Identify what type of programming that you are performing.
  20. • Normal--This type of programming is for updating an existing calibration or programming a new controller.
    • Vehicle configuration index (VCI)--This selection is used if the vehicle VIN is unavailable or not recognized by the Techline terminal. Observe, you will need to contact the Techline Customer Support center to use this option.
    • Reconfigure--This is to reconfigure a vehicle, such as tire size and axle ratio changes.
  21. Select the appropriate calibration file.
  22. Ensure all connections are secure.
  23. Select Reprog to initiate the download of the new calibration to the Tech 2.
  24. After the download is complete, turn OFF the Tech 2.
  25. Disconnect the Tech 2 from the Techline terminal.
  26. Install the Tech 2 to the data link connector (DLC).
  27. Turn ON the Tech 2.
  28. Turn ON the ignition, with the engine OFF.
  29. Select Service Programming.
  30. Important: DO NOT turn OFF the ignition if the programming procedure is interrupted or unsuccessful. Ensure that all the PCM and DLC connections are secure and the Techline operating software is up to date. Attempt to reprogram the control module. If the control module cannot be programmed, replace the control module. Refer to Powertrain Control Module Replacement

  31. Select Program.
  32. After the download is complete, EXIT Service Programming.
  33. Turn OFF the ignition for 30 seconds.
  34. Turn OFF the Tech 2.
  35. If a control module is replaced the following service procedures must be performed:
  36. • The Crankshaft Variation Learn Procedure
    • The Engine Oil Life Reset Procedure
    • The Idle Learn Procedure
    • The Inspection/Maintenance Complete System Set Procedure
    • The Vehicle Theft Deterrent Password Learn Procedure
    • The throttle position (TP) Sensor Learn Procedure

Programming Verification

  1. With a scan tool, clear the DTCs.
  2. Attempt to start the engine.
  3. Repeat the Service Programming procedure if the engine does not start or operates poorly. Perform the following procedures before programming the PCM:
  4. • Ensure the control module and DLC connections are OK.
    • Ensure the Techline operating software is up to date.
    • Ensure the calibration part number is correct for the vehicle.
  5. Attempt to program the control module. If the control module still cannot be programmed properly, replace the control module. Refer to Powertrain Control Module Replacement You must program the replacement control module.