Service Repair

Fanning Issues for Hybrid Buick

Sept. 13, 2021

This bulletin applies to 2012-2016 Buick Lacrosse Regal and Lacrosse eAssist vehicles.

This bulletin applies to 2012-2016 Buick Lacrosse Regal and Lacrosse eAssist vehicles. The drive motor-generator and battery control module (Hybrid powerpack) cooling fan may become inoperative due to low system voltage. There may have been a charging system message, battery warning lamp or service hybrid system message displayed and may have DTCs P0C32 (hybrid/EV battery pack cooling system performance) and P0A7E (hybrid/EV battery pack high temperature) stored.

If the voltage level drops to a predetermined level below approximately 9V, use GDS2 to command the battery pack cooling fan motor on to make sure it operates. If the fan operates, reprogram the generator control module. If the fan does not operate, replace the fan.

In order to test the fan, follow these steps:

Start GDS2 and enter the correct vehicle information. Make sure that Engine RPO “LUK” is selected.

Select Module Diagnostics.

Select the Hybrid Powertrain Control Module (HPCM).

Select Control Functions.

Select the Hybrid/EV Battery Pack Cooling Fan.

Command the fan on. Listen for fan operation and monitor fan speed.

Command the fan off.

Start the engine and monitor the hybrid battery pack voltage, current and state of charge (SOC) in the HPCM data list.

Exit GDS2.

About the Author

Information courtesy of Mitchell 1

Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.

About the Author

Mike Mavrigian | Motor Age Editor

Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety of specialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.