Service Update for Inventory Vehicles Only-Improved ECM Calibration-Reprogram ECM-Expires March 5, 2007

THIS SERVICE UPDATE INVOLVES VEHICLES IN DEALER INVENTORY ONLY AND WILL EXPIRE MARCH 5, 2007.

This bulletin provides a service procedure to reprogram the Engine Control Module (ECM) on certain 2007 Chevrolet Silverado and GMC Sierra vehicles, equipped with a 6.6L Duramax Diesel V8 (RPO LMM - VIN 6) engine, in order to provide improved calibrations.

This service procedure should be completed on involved vehicles currently in dealership inventory as soon as possible, but no later than March 5, 2007, at which time this bulletin will expire.

A list of involved vehicles currently in dealer inventory is attached to the Administrative Message (GM) or Dealer Communication (Canada) used to release this bulletin.

Important: Dealers are to confirm vehicle eligibility prior to beginning repairs by using the GM Vehicle Inquiry System (GMVIS).

Do not attempt to order the calibration number from GMSPO. The calibration numbers required for this service procedure are programmed into control modules via a Techline Tech 2® scan tool and the Techline Information System (TIS) 2000 terminal with the calibration update. Use data version 2.5 for 2007 or later, available on TIS 2 Web (website version of TIS) February 18, 2007; and on TIS DVD version 3.0 / 2007 or later, mailed to dealers beginning March 14, 2007. Contact the Techline Customer Support Center at 1-800-828-6860 English or 1-800-503-3222 French to obtain the correct calibration until the February 18, 2007 TIS 2 Web update.

The "Required Field Actions" section of the GM Vehicle Inquiry System (GMVIS) must be checked to determine if a specific vehicle requires this action. If GMVIS indicates that Service Update Bulletin 07039 remains ‘open’ and ECM reprogramming has not taken place, reprogram the ECM using a Tech 2® scan tool with the calibration update from Techline Information System (TIS) 2000.

Notice: Before reprogramming, please check the battery condition to prevent a reprogramming error of any of the modules due to battery discharge. Battery voltage must be between 12 and 16 volts during reprogramming. If the vehicle battery is not fully charged, use jumper cables from an additional battery. Be sure to turn off or disable any system that may put a load on the battery, such as automatic headlamps, daytime running lights, interior lights, heating, ventilation, and air conditioning (HVAC) system, radio, engine cooling fan, etc. A programming failure or control module damage may occur if battery voltage guidelines are not observed.

The ignition switch must be in the proper position. The Tech 2® 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.

Make certain all tool connections are secure, including the following components and 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.

DO NOT turn OFF the ignition if the programming procedure is interrupted or unsuccessful. Ensure that all control module and DLC connections are secure and the TIS terminal operating software is up to date.

Tech 2 Pass-Thru Method for the Engine Control Module (ECM)

1. Verify that there is a battery charge of 12 to 16 volts. The battery must be able to maintain a charge during programming. Use an additional jump battery if necessary.
2. Connect the Tech 2 to the vehicle and the TIS terminal.
3. Turn the ignition to the ON position with the engine off.
4. After all warning chimes inside the vehicle have stopped, turn on the Tech 2.
5. On the TIS terminal go into SPS Programming.
6. Select Pass Thru programming.
7. Follow instruction on the TIS terminal. When you get to the Supported Controllers screen.

7.1.	Scroll down in the top box and select ECM (Engine Control Module).

7.2.	In the middle box select Program ECU.

7.3.	In the lower box select Normal.

7.4.	Select Next.

8. Select NEXT when the calibrations screen displays.
9. Follow on screen prompts until programming is completed.
10. When programming is complete:

10.1.

Turn off Tech 2.

10.2.

Turn the ignition switch to the OFF position.

11. Wait 30 seconds.
12. Turn ignition switch to the ON position with engine off.
13. Turn on the Tech 2.
14. Go into diagnostics and check for DTC codes.
15. Clear all codes.

For vehicles repaired under this service update, use: