Headlight switch dimmer question

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Ellie Niner

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Okay. It sounds like you may have left and right brake or turn signal circuits shorted together somewhere. Here's a couple tests to help narrow it down: does the turn signal flasher still flash the lights when the parking lights are on? Does the hazard flasher work (the actual button on the right side of the steering column)? It should stop flashing and all four corners illuminate steadily when you step on the brake. With the ignition switch off, step on the brake pedal... both brake lights should illuminate. Keeping the ignition off and with your foot on the brake, turn on the left turn signal... the left brake light should go out. Repeat for the right turn signal... right brake light should go out. If either of the green turn signal indicators on the dash come on (along with front turn signal) when doing this, you've got the two sides shorted together at some point.
 

squarelyfe

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Okay. It sounds like you may have left and right brake or turn signal circuits shorted together somewhere. Here's a couple tests to help narrow it down: does the turn signal flasher still flash the lights when the parking lights are on? Does the hazard flasher work (the actual button on the right side of the steering column)? It should stop flashing and all four corners illuminate steadily when you step on the brake. With the ignition switch off, step on the brake pedal... both brake lights should illuminate. Keeping the ignition off and with your foot on the brake, turn on the left turn signal... the left brake light should go out. Repeat for the right turn signal... right brake light should go out. If either of the green turn signal indicators on the dash come on (along with front turn signal) when doing this, you've got the two sides shorted together at some point.
I'll hit this battery of tests tomorrow, thank you again for checking back with the help! After getting 90% of it back I'm throwing down a couple of fireball shots and having a twisted tea :)
 

squarelyfe

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About to dig in
 
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squarelyfe

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Starting with: no power just pushing the flasher hazard in, all four flash with the hazard mode.

With key on: turn signaling only the rear right and left work as they should. Front both come on at the same time L+R basically flashing in Hazzard mode while the rear is functioning properly. It's leading up front but where to go from here?
 

squarelyfe

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Okay. It sounds like you may have left and right brake or turn signal circuits shorted together somewhere. Here's a couple tests to help narrow it down: does the turn signal flasher still flash the lights when the parking lights are on? Does the hazard flasher work (the actual button on the right side of the steering column)? It should stop flashing and all four corners illuminate steadily when you step on the brake. With the ignition switch off, step on the brake pedal... both brake lights should illuminate. Keeping the ignition off and with your foot on the brake, turn on the left turn signal... the left brake light should go out. Repeat for the right turn signal... right brake light should go out. If either of the green turn signal indicators on the dash come on (along with front turn signal) when doing this, you've got the two sides shorted together at some point.
With the lights on, Hazzard mode/ flash mode up front from turn signal action.

When I brake and hear the click the flash mode does stop.

With key off, press the brake pedal and hit left flash, it goes out. When I press the brake pedal and signal right I believe it's going out.
 
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Ellie Niner

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With the lights on, Hazzard mode/ flash mode up front from turn signal action.

When I brake and hear the click the flash mode does stop.

With key off, press the brake pedal and hit left flash, it goes out. When I press the brake pedal and signal right I believe it's going out.
Those tests eliminate the possibility of the rear lighting harness being shorted together (yellow wire for left brake/turn & dark green wire for right brake/turn)... but I'm not 110% sure on the front lighting harness (light blue for left turn & dark blue for right turn), so you might want to physically check the condition of those wires from the switch to the park/turn signals. If that fails to reveal anything, the turn signal switch itself might be screwed up. After that, I'm fresh out of ideas.

And none of these test results hold water if there's LED bulbs in the circuit, as those have voodoo inside and can bork things in mysterious ways.
 

squarelyfe

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No led, I did decide to remove the Hazzard flasher relay to see if it would have any effect. I lost everything. Got it back and same stuff. Maybe my problem is between there and the cam. This sucks! What is the rectangular black looking relay box?
 

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Raider L

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@squarelyfe,

Your turn signals are controlled through the circuits in the turn signal electrics in the steering column under the steering wheel. It's like changing out your turn signal cam, that wiring. You may have a break in that cam that makes your turn signals work. If that wiring is somehow damaged you'll have turn-hazzard problems. Have you messed with the turn signal mechanism in the column lately? How about the wiring that runs up the column from that wiring on top of the column where your ignition switch is. There is this flat piece of plastic that has a bunch of wires in it. You have to slip it off a metal bracket on the column to get it loose enough, to be able to pull it out in order to get to the upper column housing and move it off. All your turn signal/hazzard wiring is in there.
Have you done anything with that flat black piece of plastic and wiring on the column lately?
Pulled on it or anything?
 

squarelyfe

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A couple of years ago I replaced the cam switch. Being that switch controls hazard and signaling I thought the same thing. Feel like my problem is between the cam switch the column fuse panel and the front lighting circuit. Still it could be a relay ground flasher uggg. One thing that I was revisiting was on the Hazard relay. One thing that happened originally was the hazard relay tabs were loose on the relay causing a short and heating the wire so I cut it and made a jumper with clean F contact to put into the panel slot.ended up splicing a piece of wire up with a connector so I could push the prong onto the relay tab on one side. Either way my rear part of lighting is working and flashing properly I'm also flashing on and off as it should it's just not doing it in the right mode in the front it's not canceling one side. So it goes back to feeling like it's in the switch or the relay. Tomorrow I'm going to clean up one more ground that i didn't get to today. One of the chassis electrical schematics I was looking at shows from the battery - to chassis ground but that the headlight wires also grounded up front. What I have is a ground on each part of the core panel and my extra wire for ground coming off the battery going to that core being that ground isn't directional I would think that would work. I do have the cab to valve cover bolt ground and main neg strap to the block instead of the alternator bracket.




@squarelyfe,

Your turn signals are controlled through the circuits in the turn signal electrics in the steering column. You may have a break in that cam that makes your turn signals work. If that wiring is somehow damaged you'll have turn-hazzard problems. Have you messed with the turn signal mechanism in the column lately? How about the wiring that runs up the column from that wiring on top of the column where your ignition switch is. There is this flat piece of plastic that has a bunch of wires in it. You have to slip it off a metal bracket on the column to get it loose enough to be able to pull it out in order to get to the upper column housing off. All your turn signal/hazzard wiring is in there.
Have you done anything with that flat black piece of plastic and wiring on the column lately?
Pulled on it or anything?
 
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squarelyfe

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Tried swapping the signal relay for Hazzard relay, makes no difference. Cleaned both front headlight grounds. One was kinda nasty so I cut it back and crimped a new contact. Made no difference. I mean it can only leave the signal cam or the front parking light sockets not making contact well for ground but would think they would be dim, flickering or not working if the grounding was an issue. They are bright and definitely ALL working, just not independent of each other.

So cam/wiring or front harness?
 
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squarelyfe

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I'm gonna look closer at the bulkhead tabs for the front circuit and do more cleaning. Is it possible for a turn switch to fail for only the front circuit, but not rear turn signals? This is very much starting to piss me off
 

squarelyfe

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Went through the front wire harness, no bare on bare or burns against wire to wire. It's gotta be the switch or wires from switch to panel to be continued..
 

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Hazards working? But turnsignal ain’t and the dash’s turn signal indicators are coming on at the same time / or staying on? Sounds like you should first make sure your lamp sockets aren’t also covered in dry n caked up grease. Distilled vinegar goes right thru all the grease ya can’t pick out with a toothpick, check your bulbs and make sure you’re using the right ones lol.
 

Ellie Niner

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I'm gonna look closer at the bulkhead tabs for the front circuit and do more cleaning. Is it possible for a turn switch to fail for only the front circuit, but not rear turn signals? This is very much starting to piss me off
A morked up turn signal switch can screw with a lot of things. I played around with a worn out turn signal switch on my Lumina, and was able to get both front turn signals and indicators to flash on a left turn (but not right turn), make the dash warning lights and seatbelt chime come on when the ignition was off, make warning lights and chime flash with the hazards...

I think you've just about narrowed it down to a bad turn signal switch.
 

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