The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - no brake lights, but the turn signal and tails lights work

jks67ss396 · 10-06-2015, 10:44 AM

ok, i think I at least diagnosed the problem

I do get 12V at white wire when brakes are pressed.

I do get flashing voltage (12V, then 0, then 12) on green and yellow (and blue and light blue) when i use the turn signal. green/yellow wires are rear taillights, blue/light blue are front blinker lights.

I do get same voltage when the hazzard is turned on.

But, I dont get voltage on the green or yellow wire when just the brakes are pressed and no turn signal

So, Im going to pull the steering wheel and see what i can see on the mechanics of the switch.

Just curious if you know this one:

Ive got a tilt column from an 80s motorhome. its got the flat connector (and theres an adapter to take the flat connector to horseshoe) and it has a black hazzard push/pull lever.

If i need to replace the turn signal switch, can i use the "correct" one for a 71 C10 with tilt? Or do i have to go get the motor home one? I would imagine i could handle the wiring, but its the hazzard button im not sure of.

Any ideas?

thanks guys!! youve been a huge help!!!

10-06-2015, 10:44 AM	#6
jks67ss396 Registered User Join Date: Nov 2012 Location: DFW, TX Posts: 295	Re: no brake lights, but the turn signal and tails lights work ok, i think I at least diagnosed the problem I do get 12V at white wire when brakes are pressed. I do get flashing voltage (12V, then 0, then 12) on green and yellow (and blue and light blue) when i use the turn signal. green/yellow wires are rear taillights, blue/light blue are front blinker lights. I do get same voltage when the hazzard is turned on. But, I dont get voltage on the green or yellow wire when just the brakes are pressed and no turn signal So, Im going to pull the steering wheel and see what i can see on the mechanics of the switch. Just curious if you know this one: Ive got a tilt column from an 80s motorhome. its got the flat connector (and theres an adapter to take the flat connector to horseshoe) and it has a black hazzard push/pull lever. If i need to replace the turn signal switch, can i use the "correct" one for a 71 C10 with tilt? Or do i have to go get the motor home one? I would imagine i could handle the wiring, but its the hazzard button im not sure of. Any ideas? thanks guys!! youve been a huge help!!!