Service of the PCM should normally consist of either replacement of the PCM or EEPROM programming. If the diagnostic procedures call for PCM replacement, check the PCM first to see if it is the correct part. If the PCM is faulty, 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 the EEPROM 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.

There are no user serviceable parts in this PCM. The PCM should never be opened for any reason.

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.

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. Remove the left strut brace.
4. Loosen the band clamp (2) at the throttle body (1) and disconnect the air duct (3) from the throttle body.
5. Disconnect the IAT sensor and the MAF sensor electrical connectors.



6. Loosen the PCM/air cleaner cover retaining screw (2).
7. Remove the PCM/air cleaner cover (1) and lift the PCM (3) from the housing assembly.



8. Disconnect the harness connectors (2) from the PCM (1).
9. Remove the PCM from the engine compartment.

1. Install the connectors (2) to the PCM (1).



2. Install the PCM (3) into the PCM/air cleaner housing assembly.
3. Install the PCM/air cleaner housing cover (1).
4. Tighten the PCM/air cleaner cover retaining screw (2).



5. Reconnect the air duct (3) to the throttle body (1) and tighten the band clamp (2) at the throttle body .
6. Reconnect the IAT sensor and the MAF sensor electrical connectors.
7. Install the strut brace.
8. Connect the negative battery cable.
9. If a new PCM is being installed, program the EEPROM.

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:

Important: The following procedure must be performed in order to prevent the odometer from incrementing up to 16 miles when the PCM is re-flashed.

1. Park the vehicle.
2. Connect the Tech 2.
3. Build the vehicle within the powertrain area of the Tech 2.
4. Select Special Functions.
5. Select Output Controls.
6. Scroll to Oil Life Reset.
7. On the Tech 2 screen, the actual oil life remaining is in the upper right corner. Select up or down 2% of the oil life, I.E. 18 percent left, enter 16 percent or 20 percent with the numeric key pad and then select Perform Reset.
8. With the ignition key on, read the amount of engine oil life remaining with the Tech 2.
9. Turn the ignition key off for ten seconds.
10. Turn the ignition key on and re-flash the PCM per the re-flash procedure.

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 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.

•	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.

20. Select the appropriate calibration file.
21. Ensure all connections are secure.
22. Select Reprog to initiate the download of the new calibration to the Tech 2™.
23. After the download is complete, turn OFF the Tech 2™.
24. Disconnect the Tech 2™ from the Techline™ terminal.
25. Install the Tech 2™ to the data link connector (DLC).
26. Turn ON the Tech 2™.
27. Turn ON the ignition, with the engine OFF.
28. Select Service Programming.

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 Removal and Installation procedures in this section.

29. Select Program.
30. After the download is complete, EXIT Service Programming.
31. Turn OFF the ignition for 30 seconds.
32. Turn OFF the Tech 2™.
33. If a control module is replaced the following service procedures must be performed:

•	Crankshaft Position System Variation Learn

•	GM Oil Life System - Resetting

•	Inspection/Maintenance Status Resetting

•	Programming Theft Deterrent System Components

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:

•	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.

4. Attempt to program the control module. If the control module still cannot be programmed properly, replace the control module. Refer to Removal and Installation procedures in this section. You must program the replacement control module.

Important: 

Ensure that all connections are secure at the following locations:

Important: The following procedure must be performed in order to prevent the odometer from incrementing up to 16 miles when the PCM is re-flashed.

1. Park the vehicle.
2. Connect the Tech 2.
3. Build the vehicle within the powertrain area of the Tech 2.
4. Select Special Functions.
5. Select Output Controls.
6. Scroll to Oil Life Reset.
7. On the Tech 2 screen, the actual oil life remaining is in the upper right corner. Select up or down 2% of the oil life, I.E. 18 percent left, enter 16 percent or 20 percent with the numeric key pad and then select Perform Reset.
8. With the ignition key on, read the amount of engine oil life remaining with the Tech 2.
9. Turn the ignition key off for ten seconds.
10. Turn the ignition key on and re-flash the PCM per the re-flash procedure.

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.

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.

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