2004 ENVOY, brake lights do not work, but the third brake light is working, the 10amp fuse under the back seat is good, the 25 amp under the hood is good. third light works so that tells me brake light switch is working. All lights, hazards, turn, running all work, Just the brake lights don't work. any suggestions where to look? Thanks in advance Mike

This has amber turn signals and hazard flashers, correct?

Have you replaced the brake light bulbs?

UR correct on the amber turns, just the brake lights quit working, no I have not replaced the bulbs. what is the percentage that both of the brake light circuits went out on both bulbs at once.

no i have not replaced the bulbs, what is the percentage of both bulbs going bad at the same time? yes on the amber turns.

Operation CHARM: Car repair manuals for everyone.
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Exterior Lights Schematics

Exterior Lights Schematics

Park Lamp Relay






Marker and Front Park Lamps






Clearance, License, and Rear Park Lamps






Stop Lamps






Turn Signal/Hazard Controls and Cornering Lamps






Left Turn Signals






Right Turn Signals






Backup Lamps






Trailer Wiring





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You would be surprised. Happens frequently. They share the same circuit and if it gets a shock from somewhere, well.

ok will change them tomorrow, Thanks

yup changed the bulbs and all good again. Thanks

Often what happens is one goes out, goes unnoticed for days/weeks/month/years, then the other goes out.

Glad you got it figured out!