Blinker dash lights on when I turn headlights on

[bob8619]

I'm finishing up my cab swap and I discovered that when I turn my head lights on, my turn signal lights on the dash light up and the turn signals wont work when this happens either. Its not bleeding through, the bulbs are actually coming on. I suck at electrical stuff so I don't know if this is a ground issue or what.

[Steeveedee]

Probably not a ground issue. You have power getting fed to them from somewhere. You're going to have to look for where a wire from the light switch to the power wires for the turn signal wires are making a connection. It's odd that both are coming on. If it was just one I'd say a shorted bulb was the cause, but it's pretty unlikely that two would be defective this way.

[bob8619]

I found the two wires that send voltage to the turn signal dash lights when you turn your blinkers on (left and right). Its a dark blue wire and a light blue wire, number 9 and 10 on the wiring harness that goes into the back of the dash cluster They get voltage on and off as they should when I flip my blinker lever left and right.

But yeah when I flip the headlights on those same two wires then have constant power, hence the blinker lights staying lit. It turns out the turn signals do in fact work when my headlights are on, they are just slower to blink. I disconnected the wiring from the column to see if maybe something inside there was letting power to feed through but the problem remains.

Does anyone know for sure if those two wires (#9 and 10) go anywhere other than the turn signal switch that is inside the column?

[franken]

The headlight switch should be grounded, the gauge panel should be grounded and the cab should be grounded. The engine should be grounded to the big - battery cable.

[LockDoc]

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I would check the ground straps before I started chasing other stuff. They probably need to be checked anyway..... Read through this thread.

http://67-72chevytrucks.com/vboard/s...d.php?t=422234

LockDoc

[bob8619]

I checked my grounds and they seemed good to me but maybe I'll redo them. I just noticed though that if I stomp on the floor , the lights go out and it works as it should until I turn the head lights off and on again.

[yuccales]

High beam switch going bad? Dome light wire shorted out under floor mat? Just guessing, good luck.

[VetteVet]

The two wires you are describing are the front turn signal wires. Light blue for the left and dark blue for the right. The main wires exit the turn signal switch harness and go to the inside cab block behind the fuse panel.
Some of the trucks have the dash turn light wires connect right at the TS switch harness with the LB and DB wires and some of the trucks have the dash lights turn signal wires connected at the block behind the fuse panel.

Here's a diagram.

This is off the TS switch harness.



The blue wires are the top four on the harness connector.

Here is the connections if they join at the inside firewall block. follow the wires from the harness connector in the upper right LB and DB down to the lower left to the block where they would join with the wires that go into the engine bay and up to the front turn signal lights.




The short blue wires off the TS harness plug go up into the dash cluster to power the turn signal lights.

[bob8619]

Fixed. I forgot that I had unbolted the front turn signals from the grille, I reattached them now it works properly.

[LockDoc]

Originally Posted by bob8619

Fixed. I forgot that I had unbolted the front turn signals from the grille, I reattached them now it works properly.

Good deal. Always nice to end up with an easy fix....

LockDoc