Service Update for Inventory and Customer Vehicles - Incorrect Speedometer Calibration - Expires with Base Warranty

THIS SERVICE UPDATE INCLUDES VEHICLES IN DEALER INVENTORY AND CUSTOMER VEHICLES THAT RETURN TO THE DEALERSHIP FOR ANY REASON, AND WILL EXPIRE AT THE END OF THE INVOLVED VEHICLE'S NEW VEHICLE LIMITED WARRANTY PERIOD.

This bulletin provides a service procedure to reprogram the instrument panel cluster. These vehicles may have an incorrect speedometer calibration. On vehicles with this condition, the vehicle speed would be up to 7 kilometers per hour slower than what is shown on the speedometer.

A list of involved vehicles currently in dealer inventory is attached to the Dealer Communication (Canada) used to release this bulletin. Customer vehicles that return for service, for any reason, and are still covered under the vehicle's base warranty, and are within the VIN breakpoints provided below, should be checked for vehicle eligibility in the appropriate system listed below.

Important: Dealers are to confirm vehicle eligibility prior to beginning repairs by using the GM Vehicle Inquiry System (GMVIS). Not all vehicles within the above breakpoints may be involved.

No parts are required for this program.

Important: The Tech 2 diagnostic tool must be updated with version 27.011 or later for reprogramming the instrument panel cluster. Use TIS2Web version 11 for 2007 (available on 10/31/07) or TIS DVD 11 (available on 11/09/07). If you cannot access the Tech 2 Update , call the Techline Customer Support Centre at 1 800-828-6860 (English) or 1 800 503 3222 (French) and it will be provided.

1. Verify the Tech 2 is installed with software version 27.011 or later.
2. Connect the Tech 2 to the vehicle.
3. With ignition ON and engine OFF, navigate to the IPC Recalibration procedure by either of the following two paths:

•	Diagnostics » 2008 » LD Trk, MPV, Incomplete » GMC Truck » C or K » Sierra » Body » Instrument Panel Cluster » Module Setup » IPC Recalibration

•

OR

•	Diagnostics » 2008 » LD Trk, MPV, Incomplete » GMC Truck » C or K » Sierra » Vehicle Control Systems » Module Setup » Instrument Panel Cluster » IPC Recalibration

4. Initiate the procedure and follow the instructions as displayed on the Tech 2.

Important: The IPC Recalibration option will only appear on the scan tool if the particular instrument panel cluster that is installed in the vehicle requires this recalibration procedure. If the vehicle is showing symptoms of speedometer inaccuracy, and the proper software version is installed on the scan tool, but this IPC Recalibration option is not displayed on the Tech 2, this procedure will not correct the problem. Refer to SI for diagnostic and repair information. In this situation, submit a claim using labour code V1737 to close this service update. Submit any further diagnostic time and repair under normal warranty.

For vehicles repaired under this service update, use: