Mechanics

CHEVY BRAKE AND HAZARD LIGHTS DO NOT WORK

1999 Chevrolet Truck

Electrical problem
1999 Chevy Truck V8 Four Wheel Drive Automatic 132000 miles

I was testing for power in the bulb socket with the hazard lights on when I accidentally shorted them out. Now the hazards and the brake lights (including over-cab light) do not work, but the turn signals, parking lights and reverse lights work fine. I checked the fuses visually and with a meter and none were blown. And I swapped the break light relay with the starter relay temporarily to check it - that didn't work. Is there another fuse or switch that may have blown that I am missing?
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Pikejb
December 22, 2008.



Ok first you should check the hot wire to the stop light switch on the brake pedal. It will be orange and should have power all the time. If it don't then you need to check the stop light relay under the hood on the left near the rear of the engine compartment. Both of these also seem to be wired to the cargo lamp as well as the hazzard lights. Let me know what you find an we will go from there. Thanks and Merry Christmas

Racefan966
Dec 22, 2008.
Hello, It sounds like the brake light switch has shorted. Test the feed and exciter wires, if you have power feed but on exciter, replace the switch with new.

2CarPros Ken
Dec 22, 2008.
Update: I have replaced the brake light switch (major pain in the rear) but that didn't work. Unfortunately, I didn't have my meter w/ me and wasn't able to test the orange wire. As far as the stop light relay goes, I switched it w/ the starter relay temporarily to test it (they have the same markings so I think they are the same size), but that didn't work either. Do you think it's the circuit boards in the tail lights? But that wouldn't explain the front hazards not working. Are there any in line fuses between the lights and the front of the truck? Something has to be blown since I shorted it out, but I can't find a single fuse that is blown. I noticed another odd thing - If you let the hazard switch out fully (should be on), nothing happens. But when I start to push it back in if I hold the hazzard switch in the half-way position, one of the front lights blinks but everything else stays dead. But this only happens with the key on.

I'm off for a few days around Christmas, so I plan on getting my meter back and working on this until it is fixed. Any more thoughts would be appreciated. Thanks and Merry Christmas

Tiny
Pikejb
Dec 24, 2008.
Hi, to futher check this problem a simple test light or multi meter will be needed, we need to confirm power sources into the switch, have you checked all the bulb to make sure the correct bulbs are installed?

If ok, test the power feed into the switch that will tell us something, we can go from there.

2CarPros Ken
Dec 24, 2008.
Ok, I got my meter back and there is no power to the break light switch. The orange wire is not hot, nor are any of the others. If this means the stop light relay may be out, how do you check it?

Tiny
Pikejb
Dec 27, 2008.
And yes the correct bulbs are installed. I only replaced one bulb and I made certain that is was the correct part number bulb w/ two fillaments.

Tiny
Pikejb
Dec 27, 2008.
This is how you check the relay

http://www.2carpros.com/how_to/how_do_i_check_a_relay.htm

do you have a wiring diagram for the circuit?

2CarPros Ken
Dec 27, 2008.
The relay seems to be working. I can power up the control terminals and get continuity between the power terminals. I checked the power terminal sockets for the relay in the fuse panel and only one power terminal socket is hot. I tried pressing the brake and turning the key on, but only one terminal has power.

I do not have a wiring diagram.

Tiny
Pikejb
Dec 27, 2008.
Let me look that up, ill get right back to you

2CarPros Ken
Dec 28, 2008.
Hi, I checked it out, the power to the brake light switch comes directly from the fuse panel, so if the fuse is good and you are not getting power to the switch, a wire or connection has failed, you might have to rewire the circuit. I have in included the wiring diagram for the circuit.


http://www.2carpros.com/forum/automotive_pictures/10_wiring_1.jpg



you might need to blow up the pic to see it clearly.

2CarPros Ken
Dec 29, 2008.
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