Indicator woes

[Fraud]

So my left turn signal doesn't work...

The right one works, the hazards work (all external and dash lights), but the left doesn't... I'm thinking its the switch, and I'm intending to check continuity with a multimeter when I get a minute, but wondering what else I should check..

left/right/haz all share a fuse as far as I can tell, so shouldn't be a fuse.. Are there independent flasher cans? would an individual bulb grounding cause this? What else might be worth checking? I'd rather not pull the switch out if I can avoid it!

[Steeveedee]

Absolutely nothing? No light on the dash, no light at either end of the truck?

[Fraud]

Originally Posted by Steeveedee

Absolutely nothing? No light on the dash, no light at either end of the truck?

correct, absolutely nothing... but hazards are fine, both lights on dash, all 4 corners.

[VetteVet]

Originally Posted by Fraud

correct, absolutely nothing... but hazards are fine, both lights on dash, all 4 corners.

Unplug the column connector and connect a multimeter between the purple wire and the yellow wire in the column harness and then select the left turn on the lever checking for continuity on the ohms setting. Key off.
The yellow wire is the left turn wire in the rear.

Then check the light blue wire with the purple wire, This is the front left turn and the indicator light.

If you get no reading then the TS switch isn't connecting the left turn wires.

As a comparison test, do the same check with the dark green wire and then the dark blue wire with the lever in right turn. You will probably get a reading.

There have been cases where the turn signal contact points were dirty and a good cleaning rectified the problem.

[VetteVet]

I missed where you were going to check continuity but at least otheres know where to check.

[Jarvis-69 GMC 1500CK]

Weird question - but does your dimmer switch work properly (if not work it 10-20 times with WD-40) my 69 was showing similar symptoms ( right down to the 4 ways! even rewired the entire back half of the truck!). My dimmer was killing ALL lights- worked it a few times and fixed that AND my turn signals.

[Fraud]

Had 30mins spare this morning so tried to get at it with a multimeter. The most valuable tool so far has been the swear jar.

How the hell do you separate the half moon connector? The screwdriver stab wound under my thumb would really like to know. Why would they use a plug that you can't grab both ends of in such a small space?

[Fraud]

Even dumber question, where might I find the dimmer switch? Previous owner swapped in an aftermarket tach cluster so may not be in a logical spot

[70shortfleet]

Originally Posted by Fraud

Had 30mins spare this morning so tried to get at it with a multimeter. The most valuable tool so far has been the swear jar.

How the hell do you separate the half moon connector? The screwdriver stab wound under my thumb would really like to know. Why would they use a plug that you can't grab both ends of in such a small space?

There is a locking tab on both sides of the connector, pry out on the locking tab and pull apart you might have to do one side at a time. The dimmer switch is located on the driver side floor board and is operated by your left foot or if you are talking about dimming down the dash lights, they are dimmed by the light switch.

[In The Ten Ring]

That God my truck had turn signal problems in 1985! My brother was driving my truck then and when he'd put on a turn signal everything would blink! That annoyed my brother so much he turned down dad's offer of the truck!!! That opened the door for me and I have it now.

You'll figure out what is wrong and it will be a great learning experience for ya.

[Fraud]

Yeah I've pulled back both of the locking tabs, I just can't get my hands on both sides of the connector to get it apart, I'll give it another shot tomorrow when I can get it out of the garage and have a bit more room.

Re: dimmer switch, that makes sense, I thought it was regarding a dimmer for the dashboard lights or something rather than he high beam switch. I'll check that, been a while since I used it

[Fraud]

Switch tested out okay... Tested the other wires using the instructions in this thread while I was in there..

http://67-72chevytrucks.com/vboard/s...21&postcount=2

:/

[Fraud]

Problem solved! The side and rear signals we're swapped out for led bulbs by a previous owner, and the one in the front bumper was still incandescent... Turns out that the only reason the entire circuit worked was because the incandescent bulb had enough impedance to make the flasher can do it's thing, and said Bulb wasn't seated correctly (pins seem to have worn off oddly). Jiggled it into place and now everything works...

Downside: the next bump I drove over could jiggle it out again... Tried swapping in a newer bulb and it wouldn't go in (guessing the pins from the old bulb have worn into the grooves?) So I'll be on the lookout for a new housing...

But hey, at least I know what's going on now..

[Fraud]

Originally Posted by Fraud

correct, absolutely nothing... but hazards are fine, both lights on dash, all 4 corners.

To anyone who finds this thread in the future, don't be like me. Relying on the lights you can see on the wall of the garage is not a substitute for getting out of the car and having a proper look.