2001 Chevy Blazer

My brake and back up lights do not work but my center top brake light works. I have hazards and turn signals. What could be my possible causes.

I do not mean to sound condescending, but checking the bulbs would be step 1.

If you know anything about this subject you would know that since I have hazard and turn signals it could not possibly be a bulb. Those were checked even though I knew they could not have been the problem.

You are apparently the one with a deficit in knowledge. The hazard & turn signal filaments or bulbs are one in the same - yes. But the brake light filaments or bulbs and the reverse light bulbs are completely different. Check the bulbs.

You know I thought I would get some positive feedback at this site but I see that is obvsiouly not the case. I said I checked the bulbs.

How did you check the bulbs? You posted that they don’t light up. The brake lights and the turn signal lights are not the same things. The fact that your turn signal lights and hazards work has nothing to do with whether or not your brake lights are bad. So I’ll just ask again - how did you check the bulbs?

What the heck is “positive” feedback?

You might have a whole different problem. But the basics come first.

The owner’s manual for my 2000 Blazer lists the Tail and Stop lamps as 3057 bulbs and the turn signal lamps as 3157 NA. As Cigroller stated correctly the brake lights and the turn signals are different bulbs. I believe the 3157’s are dual filament and the 3057’s are single filament and are not interchangeable. Do you have 12 volts in the brake light socket when the brakes are applied?

Ed B.

Check the ground connections under the left rear of the truck for the rear lighting system. Both the brake and reverse light circuits use this common ground as do the other rear light circuits. from the wiring diagram, this could be a muli-wire ground connection for each circuit, or single wire ground connection for all circuits. If it’s a multi-wire connection, the circuits for the brake and reverse light grounds may be comprimized.