← Back to list

2008 Chevy Cobalt 2.2L P0571 Fault: Brake Light Issue in Park Position

Model: 2008 Chevy Cobalt Fault Code: P0571 Posted: 2012-05-16 07:42

Hi everyone, I'm experiencing a P0571 cruise control brake switch circuit fault on my 2008 Chevy Cobalt 2.2L. After inspecting the vehicle, I found that the brake lights illuminate when the gear selector is in reverse, neutral, or drive — but do not light up when the vehicle is in park, even when the brakes are pressed. The brake lights remain on continuously while in RNDL (reverse, neutral, drive, low) unless the key is turned off. This behavior suggests a problem with either the brake switch or its associated wiring circuit. I initially suspected a stuck or shorted brake switch and replaced it — no improvement. I then checked the wiring diagram and confirmed that the brake switch signal is routed to the Body Control Module (BCM), which relays it to the brake lamp bulbs. After replacing the BCM with a dealer-programmed unit, the issue persists: the brake lights still stay on in RNDL. One component in this circuit is integrated into the fuse panel relay — I'm unsure how to properly test that for continuity or faults. The only other possibility I can think of is a wiring short between the brake switch circuit and a power source that activates during RNDL but not in park. Any insights, troubleshooting steps, or known fixes for this P0571 issue on the 2008 Chevy Cobalt 2.2L would be greatly appreciated! - Justin

Related fault codes
P0571
Comments (3)
Anonymous 2012-05-16 10:20

I'm taking my vehicle to an electrical specialist for a full diagnostic — will update with findings in case it helps others facing the same issue.

Anonymous 2012-05-17 05:12

The most likely cause is a wiring harness short, especially near the gear shift column. That's where the brake light circuit and shifter interlock signals typically converge. I've seen similar issues in Dodge vehicles — brake lights stay on even without pressing the pedal or engaging the switch.

Anonymous 2012-06-22 14:53

I replaced both the BCM and the brake switch, though I suspect only the switch needed replacement. The Chevy dealer I used mentioned they had to reprogram the gear position settings in the brake switch module. However, after the BCM replacement, I started experiencing AC issues — turns out there are two different BCM versions for this model year, and I received the wrong one. This is a valuable lesson for anyone troubleshooting P0571 symptoms on a 2008 Cobalt.