System Software Upgrade-OBD System Software Upgrade-OBD System Improvements (Reprogram Powertrain Control Module (PCM))

This bulletin provides information about installing new Powertrain Control Module (PCM) software and calibration on certain involved 2006 Chevrolet Silverado chassis cab, Suburban, Avalanche; GMC Sierra chassis cab and Yukon XL model trucks, equipped with dual fuel tanks. The revised calibration includes OBD system improvements that affect the fuel level sender diagnostics that should be installed as soon as practical. Install the new calibration on all affected vehicles identified in this bulletin, including vehicles in new dealer inventory and any vehicles that return for service, for any reason, during the applicable 8 year / 80,000 mile (130,000 km) emission controller warranty coverage period. To verify if an updated calibration is required, refer to the following procedure in this bulletin.

Important: A VIN list of involved vehicles currently in dealer inventory/stock is attached to the Administrative Message used to release this bulletin.

Do not attempt to order the calibration number from GMSPO. The calibration numbers 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 2006 or later, broadcast to dealers on February 19, 2006; and on TIS CD-ROM version 3.0 / 2006 or later, mailed to dealers beginning on March 15, 2006. If you cannot access the calibration, call the Techline Customer Support Center at 1-800-828-6860 and it will be provided.

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 System Software Upgrade 06505 remains ‘open’ and PCM reprogramming has not taken place otherwise after the TIS Broadcast or CD-ROM availability dates identified in this bulletin, reprogram the PCM using a Tech 2 scan tool with the calibration update from Techline Information System (TIS) 2000.

Tech 2® Remote Programming Method for PCM

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.

1. Verify the battery charge of 12 to 16 volts. The battery must be able to maintain the charge during programming. Use an additional jump battery if necessary.
2. Use the normal "request method" through "Service Programming System" to request information from the vehicle.
3. At the Techline Terminal, enter TIS SPS programming system.
4. Select Tech 2® from the "Select Diagnostic Tool" window.
5. Select Reprogram ECU from the "Select Programming Process" window.
6. Select Vehicle from the "Select ECU Location" window.
7. Select Next to go to the "Preparing for Communication" instruction screen.
8. Select Next to view the "Validate Vehicle ID Number" screen. If the vehicle ID number does not appear on the screen, manually insert the VIN into the VIN window of the "Validate Vehicle ID Number" screen.
9. Select Next to view the "Supported Controllers" screen.
10. Select PCM/VCM Powertrain/Vehicle Control Module from "Supported Controllers" window.
11. Select Next to view the "Select Programming Type" window.
12. Select Normal from the "Select Programming Type" window.
13. Select Next to view the "Service Programming System Calibration Selection" screen.
14. Select Next to view "Summary" screen.
15. Verify that current and selected calibration information is displayed on the "Summary" screen.
16. Select Next to download the calibration to the Tech 2®.
17. Back at the vehicle, enter "Service Programming Systems".
18. Select Program ECU and follow the on-screen instructions.
19. When programming is complete, do the following:

19.1.

Turn the Tech 2® OFF.

19.2.

Turn the ignition switch OFF.

20. Wait 30 seconds.
21. Turn the ignition switch to ON with the engine OFF.
22. Go into Diagnostics and check for DTC codes.
23. Clear all codes.

For vehicles repaired under the 8 year/80,000 mile (130,000 km) emission controller warranty use: