Rear brake lights not working

[GregGnTn]

My third brake light works, my parking lights work but no brake lights on ether side, I have cleaned the the light bulbs sockets and light switches prongs out of the dash and new bulbs ??? Thanks Greg

 

[1986 Buick GX1]

It may be a bad brake light switch at the pedal.
There’s two circuits built into the one switch.
One for the third brake light and one for the regular brake lights.

 

[salvageV6]

Brake light issues

Last summer I started having issues with my brake lights. After much reading, I thought the problem was my turn signal stalk. After replacing that the brake lights were working and I thought I was all good. After taking the car out of storage, the brake lights once again do not work. The...

turbobuick.com

 

[GregGnTn]

It may be a bad brake light switch at the pedal.
There’s two circuits built into the one switch.
One for the third brake light and one for the regular brake lights.

I will try this , I was thinking if the third light was working then it couldn’t be that, thanks Greg

 

[1986 Buick GX1]

I will try this , I was thinking if the third light was working then it couldn’t be that, thanks Greg

I had an ‘84 cutlass ciera do the same thing on a trip. I stopped at a GM dealership on the way, swapped the switch in the parking lot and was on my way.

I had the harmonica shaped connector (as savageV6 has described) not seated all the way after installing a repaired digital dash as well.

Both good places to start.

 

[precizion818]

I had issues with the brake switch (melting) and not working properly.

Also check the white wire near the bottom of the steering column on the big connector. I have had issues with the white wire not making good connection and it causing the brake lights not to work.


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[TurboBuRick]

Do your hazards work?

 

[captndave737]

here's the schematic

 

[1986 Buick GX1]

It seems chassis grounds are brought up a lot too.

 

[TurboBuRick]

Check to see if hazards are workings. That will eliminate anything being wrong with grounds and wiring.
If hazzarda work the problem is more than likely the turn signal switch in the column.

Rick

 

[GregGnTn]

Do your hazards work?

Yes all hazards work..

 

[TurboBuRick]

Then your grounds and wiring are ok. The hazards use the same circuit.

Your problem is the turn signal switch inside the column. Have to pull the steering wheel to replace it.

 

[GregGnTn]

Then your grounds and wiring are ok. The hazards use the same circuit.

Your problem is the turn signal switch inside the column. Have to pull the steering wheel to replace it.

Should I try the brake switch first? And not how hard is it to pull the steer wheel ? Thanks Greg

 

[precizion818]

Should I try the brake switch first? And not how hard is it to pull the steer wheel ? Thanks Greg

Being that I just had brake switch problems.... I would check it first. Would also check the connector as well. Both were melted on my car.

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[TurboBuRick]

It won’t hurt to check

 

[GregGnTn]

Being that I just had brake switch problems.... I would check it first. Would also check the connector as well. Both were melted on my car.

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Okay how did you get this off I can unplug one side, the other side I can’t see to unplug, then if I do get it unplugged how do you unscrew it ? Thanks Greg

 

[salvageV6]

Get a meter or test lamp out and check the white wire on the brake switch with the brake light switch ON, you can either use the pedal, push to test, or pull the switch out to get at the wires easier and it should stay on as long as you have it out of its mounting.

If that white wire has power on it go up to the harmonica connector as mentioned a long time ago...

The test you have done with the Hazard switch proves the grounds and lights are good out back there is nothing wrong with the hazard switch and brake light wiring to the rear of the car.

It's about 1/2 hours worth of work....

 

[GregGnTn]

Get a meter or test lamp out and check the white wire on the brake switch with the brake light switch ON, you can either use the pedal, push to test, or pull the switch out to get at the wires easier and it should stay on as long as you have it out of its mounting.

If that white wire has power on it go up to the harmonica connector as mentioned a long time ago...

The test you have done with the Hazard switch proves the grounds and lights are good out back there is nothing wrong with the hazard switch and brake light wiring to the rear of the car.

It's about 1/2 hours worth of work....

 

[GregGnTn]

Okay I have both plugs unplugged, how do you unscrew looks like there is a tab or a washer holding it on ?

 

[salvageV6]

Since you have the connectors off the switch use a jumper wire to short the Orange wire to the White wire. That will simulate a brake pedal press, Orange wire is always hot so be careful and don't short it to ground, it goes to the STOP/HAZ fuse. The light blue wire is the 3rd brake light wire which works so no need to check that.

If the lights work the switch is bad if they don't work you need to check the white wire at the harmonica connector attached to the steering column on the right side as you face the windshield.

Easiest access to it is by removing the A/C lower vent plastic piece, a couple of screws and you probably already have the lower black plastic trim piece off if not it has to come off too, 2 screws and a nut down by the gas pedal.