GM Service Manual Online
For 1990-2009 cars only

Powertrain Control Module Programming Offboard

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 customer's concern.
   • The Off-Board Programming is used in situations where a control module must be programmed without having the vehicle present. The Off-Board Programming Adapter must be used to perform the Off-Board Programming procedure. The adapter allows the control module to power up and allows the Tech 2 to communicate with the control module.
   • DO NOT disturb the tool harnesses while programming. If an interruption occurs during the programming procedure, programming failure or control module damage may occur.

Ensure that all connections are secure at the following locations:

    • The Off-Board Programming Adapter
    • The Tech 2
    • The control module
    • The Techline terminal

Off-Board Programming

  1. Obtain the VIN of the vehicle for which the control module is being programmed.
  2. With the Techline terminal, select Service Programming.
  3. Select Tech 2, Reprogram ECU, and Off-Board Programming Adapter as the ECU location.
  4. Connect the control module, Off-Board Programming Adapter, and the Tech 2 as described on the Techline terminal. Ensure you use the correct harness connector from the Off-Board Programming Adapter kit.
  5. With the Tech 2, select Service Programming Request Information function. The Tech 2 communicates with the control module and receives the access code.
  6. With the Tech 2, exit the Service Programming Request Information.
  7. Disconnect the Tech 2 from the Off-Board Programming Adapter.
  8. Connect the Tech 2 to the Techline terminal.
  9. Turn ON the Tech 2.
  10. With the Techline terminal, enter the VIN of the vehicle that will be receiving the control module.
  11. The Techline terminal will display the message, attaching to database.
  12. Identify what type of programming that you are performing.
  13. Select the appropriate calibration file.
  14. Ensure all connections are secure.
  15. The Techline terminal displays a summary screen that summarizes your selections. After confirming you choices, the Techline terminal automatically loads the calibration files to the Tech 2.
  16. After the download is complete, turn OFF the Tech 2.
  17. Disconnect the Tech 2 from the Techline terminal.
  18. Connect the Tech 2 to the Off-Board Programming Adapter.
  19. With the Tech 2, select Service Programming.
  20. Important: DO NOT turn OFF the Off-Board Programming Adapter if the programming procedure is interrupted or unsuccessful. Ensure the control module and the Off-Board Programming Adapter 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.

  21. With the Tech 2, select Program.
  22. After the download is complete, exit Service Programming.
  23. Turn OFF the Off-Board Programming Adapter.