This bulletin applies to 2012-2013 Buick LaCrosse vehicles. There may be an MIL on, battery Indicator or Service Charging System message on, with any combination of DTCs P1EAB, P1B33, P1B34, P1B35, P1B36, P1B37, P1B38 or P1B39.
If diagnostics lead to replacement of the Battery Energy Control Module (BECM), DO NOT replace the entire Powerpack or the BECM for this concern. The BECM should be SPS programmed with the latest software available for the BECM. If diagnostics still lead to BECM replacement, P/N 20969054 has been released for service but is currently on restriction through the General Motors Technical Assistance Center. Once installed, the BECM will need to be SPS programmed with the latest software.
NOTE: If P1EAB is set, it will be necessary to clear the High Voltage DTC using GDS2. After selecting the proper vehicle information in GDS2, follow the Navigation Path to clear the HV DTC. After the reset is selected, the ignition will need to be turned off for a minimum of two minutes.