Brake light problem for 1997 Chevy Blazer.

Hello,

I have a friend that has a 1997 Blazer and the brake lights are acting up. The main lights don't light up when you apply the brakes, but the center brake light lights up fine.:screwy: there is no power going to the main brake bulb sockets.:frown: I tested this out using a 12 volt power tester. the brake switch seems fine otherwise I would think the center brake light wouldn't light up.

The bulbs are fine for the main brake lights.

Does anyone have any advice where to look / investigate so I can fix this problem. Any help / advice is helpful.

Regards,
JOET/CAMRY

Remove the plastic panel under the dash that will let you access the brake pedal arm and the brake light switches that come in contact with it.
You'll see a little nub of plastic sticking out of each switch that the brake pedal arm pushes. Push each little nub back inside their switch housing pull away to the side so they suddenly shoot out with their spring pressure a coupla times then check your brake lights for function.

Remove the plastic panel under the dash that will let you access the brake pedal arm and the brake light switches that come in contact with it.
You'll see a little nub of plastic sticking out of each switch that the brake pedal arm pushes. Push each little nub back inside their switch housing pull away to the side so they suddenly shoot out with their spring pressure a coupla times then check your brake lights for function.

Thanks for replying to my question Chris Stewart. the switches that you describe are not there. all I saw was only 1 switch and it was white in color and about half the size of a pack of cigarettes. It seemed to work fine and I even took it apart by (very carefully) undoing the clips and it looked like brand new inside.

I was toying around with the idea of splicing the middle brake light power to the main brake lights.:disappoin I don't know if that will work or not. I don't know what else to check. Any help/advice would be appriceated. Thank You.

Regards,
JOET/CAMRY

do the signals, and backup lights work? if they work, then it may be just the brake light wire under the back of the truck, if not, you've got a lot more wires to test. find the wire loom, and try to test the wires with your test light. If it's just the brake lights that aren't working, pull the light out so you can see what color wires you're looking for. I've seen lights go out from getting hit with a rock from the tires and such ( I go wheeling a lot with my fullsize ) check that and post back

I just went through a similiar problem with a Camaro. The wiring connector w/8 wires at the base of the steering column had a poor connection on the juice wire to the brake lights that for some reason needed to run up into the steering column. After disconnecting then reconnecting 3 or 4 times, it finally made a good connection and the brake lights started working.

Third brake light has it's own switch on the brake pedal and uses it's own wire to the rear of the vehicle. It is totally separate from the stop lamps and turn signals. Left turn and stop uses it's own wire. Right turn and stop use a different wire. Check both switches on the brake pedal. Check the 4 way hazard switch and the multifunction switch. The multifunction switch splits the turn and stop circuits.

To add a little. And hope it does not confuse you.
The brake light circuit is easy to test but trickie.
The white wire from brake light switch feed the brake light circuit.
Double check brake light switch for voltage in and out on white wire from switch.
If voltage out on white wire check for brake light voltage into turn signal switch on white wire.

If 12 volts in on white wire then check for 12 volts out of it on dark green right turn/brake light wire and for 12 volts out of it on yellow wire left brake/turn signal.
If brake light voltage out of turn signal switch on yellow right turn and yellow left turn wire.
Go to tail light and check for voltage into them and for good ground.

Note the turn signals and brake light share the same bulbs and wires to rear signals and brake lights.
When turn signals is turned on for one side the brake light switches over to the other side.

Does the turn signals work good on the rear?
A stuck on or bad 4 way flasher switch will knock out rear brake/turn signal lights.
Also inspect rear end for add on trailer plugs and bad splice in on trailer plug wiring.
Good luck
MT

is there a brake relay and if so where

Thanks for replying to my question Chris Stewart. the switches that you describe are not there. all I saw was only 1 switch and it was white in color and about half the size of a pack of cigarettes. It seemed to work fine and I even took it apart by (very carefully) undoing the clips and it looked like brand new inside.

I was toying around with the idea of splicing the middle brake light power to the main brake lights.:disappoin I don't know if that will work or not. I don't know what else to check. Any help/advice would be appriceated. Thank You.

Regards,
JOET/CAMRY

UPDATE......

The hazzard switch was bad and as a result the main brake lights would only work when I would put pressure on the hazzard switch by pulling it to the left and holding it while pressing the brake pedal.:screwy: some sort of loose connection in the switch.:shakehead I rigged up the hazzard switch with some zip ties so their is constant pressure pulling the hazzard switch knob to the left and the brake lights have been working great. just can't use the hazzard lights the way it's rigged up.:eek: a new hazzard switch is expensive.:banghead:

Why are the brake light wires connected to the hazzard switch anyway? what a odd design. :disappoin :screwy:

Regards,
JOET/CAMRY

Stop and turn signal use the same filaments in the bulb. The signal has to be split or both left and right rear turn signals would come on when you hit the brakes. Old design and still done that way. The only way around it is to use separate bulbs for stop and turn, which some cars do.

The hazard switch can be serviced separately and is not a difficult job at all. If you look in the Blazer "How To" section, there is a thread that shows how to do it.

Stop and turn signal use the same filaments in the bulb. The signal has to be split or both left and right rear turn signals would come on when you hit the brakes. Old design and still done that way. The only way around it is to use separate bulbs for stop and turn, which some cars do.

The hazard switch can be serviced separately and is not a difficult job at all. If you look in the Blazer "How To" section, there is a thread that shows how to do it.

Thank You old_master for your reply. I posted a link to the hazzard switch repair that you mentioned. I never knew the hazzard switch was repairable. thought I had to replace the entire switch. Take care.

http://www.automotiveforums.com/vbulletin/showthread.php?t=595263

Regards,
JOET/CAMRY

UPDATE......

The hazzard switch was bad and as a result the main brake lights would only work when I would put pressure on the hazzard switch by pulling it to the left and holding it while pressing the brake pedal.:screwy: some sort of loose connection in the switch.:shakehead I rigged up the hazzard switch with some zip ties so their is constant pressure pulling the hazzard switch knob to the left and the brake lights have been working great. just can't use the hazzard lights the way it's rigged up.:eek: a new hazzard switch is expensive.:banghead:

Why are the brake light wires connected to the hazzard switch anyway? what a odd design. :disappoin :screwy:

Regards,
JOET/CAMRY

UPDATE........

It has been 15 months since I rigged up the hazard switch with zip ties on my friends 1997 Chevrolet Blazer (see above post) and all was well until my friend tried to turn on the hazard switch the other day :banghead: an as a result the brake lights went out again. Then she had one of her friends try to fix it and ended up snapping it off flush.:shakehead Anyway I bought the hazard switch repair kit and installed it and all is well with the lights again.:cool: It's like brand new now. Here is the link to the post explaining the repair procedure and the hazard switch repair kit part number.

http://www.automotiveforums.com/vbulletin/showthread.php?t=595263


I did however have to call around to different GM dealerships as the local Chevrolet dealership wanted to sell the whole hazard switch at a cost of over $400.00 :screwy: They said that the repair kit was not available. :confused:
I eventually was able to buy the hazard switch repair kit for around $17.00 witch is a more reasonable price. If I knew that this repair kit would have solved the problem back in April 2008 I would have bought it back then. oh well... live and learn.:)

Regards,
JOET/CAMRY

Ty so much. This was exactly our prblm. My husband wedged a stick n the hazard light for a temporary fix. Worked like a charm.