Service Update for Inventory and Customer Vehicles-ECM DTC P1400 OBD Enhancement Calibration - Reprogram ECM

THIS BULLETIN IS BEING REVISED TO CORRECT THE SERVICE PROCEDURE. PLEASE DISCARD ALL COPIES OF BULLETIN 08288, ISSUED SEPTEMBER 2, 2008.

THIS SERVICE UPDATE INCLUDES VEHICLES IN DEALER INVENTORY AND CUSTOMER VEHICLES THAT RETURN TO THE DEALERSHIP FOR ANY REASON. IT WILL EXPIRE AT THE END OF THE INVOLVED VEHICLE'S 8 YEAR / 80,000 MILE (130,000 KM) EMISSION CONTROLLER WARRANTY PERIOD.

This bulletin provides a service procedure to reprogram the Engine Control Module (ECM) on certain 2009 Chevrolet Impala vehicles, equipped with a 3.5L (RPO LZ4 - VIN N) engine. The new ECM software and calibrations include improvements to the P1400 diagnostic that will prevent DTC P1400 from setting and illuminating the Malfunction Indicator Light (MIL) when no malfunction exists.

This service procedure should be completed as soon as possible on involved vehicles currently in dealer inventory and customer vehicles that return to the dealer for any type of service during the New Vehicle Limited Warranty coverage period.

A list of involved vehicles currently in dealer inventory is available on the "Service Update Bulletin Information" link under the "Service" tab in DealerWorld (US), or 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 GM Vehicle Inquiry System (GMVIS).

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.

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 Multiple Diagnostic Interface (MDI) or Tech 2® scan tool and TIS2WEB with the calibration update. Use TIS2WEB on or after 08/27/08 to obtain the calibration. If you cannot access the calibration, call the Techline Customer Support Center and it will be provided.

GMVIS must be checked to determine if a specific vehicle requires this action. If the system indicagtes that Service Update Bulletin 08288A remains "open" and ECM reprogramming has not taken place, reprogram the ECM using a Tech 2® scan tool or MDCI with the calibration update from TIS2Web.

Service Programming System (SPS)

For step-by-step programming instructions, please refer to SI and the Techline Information System (TIS) terminal.

1. Verify that there is a battery charge of 12 to 16 volts. The battery must be able to maintain a charge during programming. Only use an approved Midtronic 165-PSC charger to maintain proper battery voltage during programming.
2. Reprogram the Engine Control Module (ECM). Refer to SI and Service Programming System (SPS) documentation for programming instructions, if required.

2.1.	Connect the MDI or Tech 2® to the vehicle.

Important: Select J 2534 MDI or Tech 2® Legacy Pass-Thru and Reprogram ECU from the Select Diagnostic Tool and Programming Process screen. The J2534 MDI will reprogram the module in less time than the Tech 2® scan tool.

2.2.	Select ECM from the Supported Controllers screen.

2.3.	Follow the on-screen instructions.

2.4.	Select new calibration with diagnostic enhancements for DTC P1400.

3. Using the MDI or Tech 2®, clear all DTCs if required.

For vehicles repaired under this service update, use: