CUCV turn signal stumper

[Pawnshop]

The left turn signal on my M1009 has developed an annoying habit. When the Service Light switch is ON and the stock headlight plunger is in the OFF position (park and head lights OFF) the turn signals operate as normal (left blinks left and right blinks right, e flashers operate normal) When the park and/or headlights are ON the front turn signal bulb is lit at maximum brightness, the left green dash indicator is on and the left turn signal does not operate (right operates in a normal fashion). This problem was intermittent for a while but is now full time and my safety inspection is due! The headlight wiring harness was replaced with a NOS unit about three years ago and has operated as designed until now. I have checked the bulb, grounds and all of the wiring from the firewall to past the left side and all look good with no signs of wear or grounding. Has the turn signal socket failed? Is it possible I have a ground or short further down stream that is causing this? I replaced the dimmer switch a couple of months ago, could this be related?

 

[Skinny]

Replace all the bulbs and clean the sockets really well. I had so many issues with signals that illuminate for no reason or do not flash when turning before I did this.

 

[Grega]

Ive also heard issues with bad bulbs,and corroded or rusty sockets.

 

[M813rc]

I don't know if it was proximity or what, but mine did the same thing a few nights back while I was following Pawnshop to chow (two 1009s in a row with the same malfunction).
I thought the left front bulb was bad, so I pulled it. It looked good but dirty, so I cleaned it well, cleaned the socket, and replaced it. All now works as advertised.

Either that was my problem, or it was just the beginning of a replication of Pawnshop's problem. I have never had a vehicle with as many electrical issues as my 1009s.

Cheers

 

[Warthog]

A couple of known issues/solutions.

A. The ground straps on the radiator support above the headlights or the ground straps at the rear lights. I had a bad ground strap on the drivers side headlight that caused this same issue.

B. Inside the bulb sockets. The ground tab usuallly corrodes and breaks. A replacement socket usually solves the issue.

 

[Pawnshop]

The bulb and socket look new and clean. The signal works fine when the lights are off so the bulb and switch are good

 

[Warthog]

The bulb and socket look new and clean. The signal works fine when the lights are off so the bulb and switch are good

Double and triple check the ground wires for the headlights. If they are bad, the current will back flow thru the circuit and illuminate the dash turn signal bulb.

 

[Pawnshop]

The one on the core support is tight and looks clean, but I did not remove it and check. There is a wire with a spade connector that goes to a tab bolted to the frame that is tight and clean too. I disconnected that one and there was no change in function (good or bad). Could the ground for the curb side be loose and cause an issue on the driver's side?

 

[Pawnshop]

I don't know if it was proximity or what, but mine did the same thing a few nights back while I was following Pawnshop to chow (two 1009s in a row with the same malfunction).
I thought the left front bulb was bad, so I pulled it. It looked good but dirty, so I cleaned it well, cleaned the socket, and replaced it. All now works as advertised.

Either that was my problem, or it was just the beginning of a replication of Pawnshop's problem. I have never had a vehicle with as many electrical issues as my 1009s.

Cheers

Yours was not doing the same thing, just the same side. Your bulb was flickering on and off randomly, mine comes on at max intensity and stays on as long as the headlights are on.

 

[Speddmon]

There is one ground on each side of the radiator on the core support. REMOVE both of them and clean them and re-attach them.

Also, just because the sockets look good, doesn't mean that the ground tab isn't cracked and ready to break. The ground tabs on both of my front signals were intact, but almost broken all the way through...causing the exact same issue you are having.

 

[Pawnshop]

OK, I will check those points tomottow!

 

[Barrman]

Sam,
If everything works like it is supposed to with the lights off. Then goes stupid with the running lights on. The it almost for sure is the ground of one of the four running lights up front or the four rear running lights. My experience in 2 different 1009's and the Blue bomber Suburban has been the ground tabs on the inside of the bulb holder for the front running lights. The lights under the headlight you have to work at to get to of course.

A good way to check this is to remove one of them. Leave the bulb in and run a jumper wire from the ground tab which is supposed to be touching the bulb metal base to a known good ground on the truck. If everything works, you found the problem and can now trace the ground wire to find the bad spot.

If the fronts check out, move to the rear and check them.

I hope this helps. I am having intermittent issues of the same basic type with the bomber. The reverse lights come on with the tail lights. Only on some mornings and only when the running/head lights are on. Sounds like we both have some grounds to track down.

 

[Keith_J]

Great! Have this problem with The Kid's 1009. Will clean all..make that have HIM clean all. Once he gets finished with MKC's driveway cleaning.

The more work he does restoring it, the more he will value it.