On my 99 Blazer the left brake lights stopped working.
So I figured a bad bulb and replaced it. Nope not it.
Right side works good.
Used a circuit check and no power at socket. Tried to check wiring harness. Seems like right & left are wired separate. One big harness under rear carpet.
Fuses OK
Any idea what to check next??

Thanks

 

Do your hazards work? Turn signal?

How do the bulb sockets look in the back?

 

Yep hazards work and turn signal. The sockets are the 3057 flat base things, but I don't have power to the brake terminal, when brakes are applied.

It surprises everyone that Left & right turn are fused separately, are brakes lights???

 

Considering that the brake lights use the exact same bulb filament and circuitry as the turn signals, that is VERY odd...

 

I think the brown wire is turn signal & Yellow is brake.
When the brake petal is pushed only the right side gets power.
Two separate wires come from front of Blazer for the brakes.
I can't see where they start from to check connections