My brake lights don’t work and won’t shift out of park
GM has issued a technical service bulletin #08-05-22-009B to address an issue of intermittent brake light operation (Brake lights don’t work), won’t shift out of park, cruise control doesn’t work, trouble codes C0131, C0161, or C0277.
The TSB applies to the following vehicles:
2004-07 Chevrolet Malibu, Malibu Maxx
2008 Chevrolet Malibu Classic
2005-09 Pontiac G6
2007-09 Saturn Aura
Since the brake switch is involved in all of these symptoms, you may be tempted to replace it. Even after replacing the switch, you may still encounter the same problems. At that point you may suspect a faulty body control module (BCM). The TSB warns against replacing any of these parts until you first address a fretting corrosion issue in the connectors. Fretting causes high resistance in the C2 connector on pins C2-18, C2-31, and C2-59. GM advises to apply dielectric lubricant to the pins in the connector.
Using a small brush, apply a light coating dielectric grease to the terminals and then reconnect the connectors. Then drive the vehicle and see if the problem is gone. If so, fretting corrosion was the cause. To learn more about fretting corrosion, read this article
©, 2014 Rick Muscoplat