brake lights no worky!!

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Ontheboulder

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Check for power on the green and yellow wires at the turn signal switch connector while pushing the brake pedal. If not, most likely the turn signal switch is defective
Yup,that’s what I am thinking,that the switch is toast.got good power out of the brake switch but not going thru the turn switch
 

Ontheboulder

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well after a day of checking grounds, checking connections, and re-checking, I think this truck is gonna need a new turn signal switch!! oh JOY! That's where everything is leading to. with all the wires going to the rear working with the exception of the brake lights, i think that's where I am at. I can't think of anything else. if anyone has any ideas I am all ears. All 4 corners work with the exception of the brake lights,brake light switch has power in and out,just nothing thru the turn signal switch. Time for a BEER!!!!
 

Turbo4whl

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thanks to you all!!! tomorrow will be check ,double check and re-enforce all the grounds,If that fails I think I will start drinking heavily!! LOL
I was going to ask you what are we drinking, but I see in the previous post you are talking beer. There are a lot of beer drinkers here, but I thought maybe we were having Scotch?
 

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Do you have the correct lamp in the tail light socket? It should be an 1157. Sometimes, I've seen incorrect lamps or installed incorrectly. Just a quick thought.
Good call. I chased a dome and cargo light “gremlin” for several hours until I discovere the gremlin was whomever put the wrong bulb in the cargo light!
Worked but sporadically with issues.
 

rich weyand

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"I think all the grounds are good as every other light circuit is working..."

Check the grounds. When they aren't right, you get stupid results.

There are four items that need grounding, and so it takes three wires to connect them. The four items are the battery, the engine, the frame, and the cab. The three wires are:

- The small wire from the battery terminal to the radiator support cross member. (battery to frame)
- The large wire from the batter terminal to the block. (battery to engine)
- The copper braid from the passenger-side head on the engine to the firewall. (engine to cab)

That last one is sometimes missing, and all kinds of weird **** can result. You get these 'everything works fine except....' scenarios.
 

Ontheboulder

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"I think all the grounds are good as every other light circuit is working..."

Check the grounds. When they aren't right, you get stupid results.

There are four items that need grounding, and so it takes three wires to connect them. The four items are the battery, the engine, the frame, and the cab. The three wires are:

- The small wire from the battery terminal to the radiator support cross member. (battery to frame)
- The large wire from the batter terminal to the block. (battery to engine)
- The copper braid from the passenger-side head on the engine to the firewall. (engine to cab)

That last one is sometimes missing, and all kinds of weird **** can result. You get these 'everything works fine except....' scenarios.
thanks, I have checked all the points you mentioned and all are good and clean,the baffling part is that I had the left rear brake light working until I changed the turn signal flasher. since then, no brake lights even when putting the original flasher back in
 

78C10BigTen

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I was going to ask you what are we drinking, but I see in the previous post you are talking beer. There are a lot of beer drinkers here, but I thought maybe we were having Scotch?
Depends on the brand! I like scotch and bourbon lol
 

AuroraGirl

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thanks, I have checked all the points you mentioned and all are good and clean,the baffling part is that I had the left rear brake light working until I changed the turn signal flasher. since then, no brake lights even when putting the original flasher back in
If you touched the fuse block and inserted a flasher can and took one out, I would look at your fuse block for seeing if you bumped the wires around it or disturbed anything. In addition, I would check continuity across your fuses (all of them while youre in there is quick with a multimeter) because bad fuses can look good rarely but it happens. and i would have to check but i presume the fuse in question can be checked for power when the brake pedal is pushed. but i am assumign the operation of the circuit in saying that, it may differ.
 

Bruce Wingate

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what has got me stumped, is that why I had the left rear brake light working,and the right rear brake and turn not working,then by replacing the flasher i had both turn signals working but no brake lights??? The 4 ways are working fine?? just seems weird that the flasher change made this difference
Do you still have the old flasher? If you put it back in does the problem revert? You might have a bad new flasher [And its for that reason that I don't throw anything away until the job is successfully complete.]
 

AuroraGirl

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"I think all the grounds are good as every other light circuit is working..."

Check the grounds. When they aren't right, you get stupid results.

There are four items that need grounding, and so it takes three wires to connect them. The four items are the battery, the engine, the frame, and the cab. The three wires are:

- The small wire from the battery terminal to the radiator support cross member. (battery to frame)
- The large wire from the batter terminal to the block. (battery to engine)
- The copper braid from the passenger-side head on the engine to the firewall. (engine to cab)

That last one is sometimes missing, and all kinds of weird **** can result. You get these 'everything works fine except....' scenarios.
I know it wouldnt be as likely the case, but is there a wire that goes from frame to battery thats on the frame itself? I had one on the frame rail ,small gauge, and then one on the core support which is the chassis ground return path but I dont have original setup
 

AuroraGirl

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thanks, I have checked all the points you mentioned and all are good and clean,the baffling part is that I had the left rear brake light working until I changed the turn signal flasher. since then, no brake lights even when putting the original flasher back in
You keep saying you checked "all" the things but you are runnign out of things to "check" and have not IDed the issue. Have you yanked the plug on the frame from the harness on the back and checked for brake power when the pedal is depressed? That can be done with a snow brush or thing to wedge the seat if long enough or a brick easily and then the plug may be annoying to separate but it should be there.

If its there, then you know its back of the truck. if its not there its between your output to the rear and that point.
 

Ontheboulder

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I
You keep saying you checked "all" the things but you are runnign out of things to "check" and have not IDed the issue. Have you yanked the plug on the frame from the harness on the back and checked for brake power when the pedal is depressed? That can be done with a snow brush or thing to wedge the seat if long enough or a brick easily and then the plug may be annoying to separate but it should be there.

If its there, then you know its back of the truck. if its not there its between your output to the rear and that point.
I have completely disconnected the rear lights from the front of the truck.no brake light power.
 

Ontheboulder

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I

I have completely disconnected the rear lights from the front of the truck.no brake light power.
With brake pedal depressed,I have tail lights,turn signals,and 4 way flashers! No brake lights.
 

Ontheboulder

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Do you still have the old flasher? If you put it back in does the problem revert? You might have a bad new flasher [And its for that reason that I don't throw anything away until the job is successfully complete.]
I put the old flasher back in place,nothing changed
 

AuroraGirl

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I

I have completely disconnected the rear lights from the front of the truck.no brake light power.
so you have no ground attached for the wiring ?
I could be wrong but I assume the brakes need the ground on the back too? I guess I never tried without that.
 

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