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Signal light issue!

Dirky

1,320
82
Turn signals work when the light switch is off (key on), but when I pull the light switch out, both filaments on the LF bulb light up, and it will not blink. Grounds are good, sockets are good, turn signal switch is new, and functions correctly.

Also, the turn signal indicator on the dash lights up when I pull the light switch out, stays lit until I push the switch back in...

Right now there is no reverse light socket on RR, but I don't think that should play a factor.

I don't get it!
 
Last edited:

Dirky

1,320
82
Better description of what's going on...

I turn on my light switch, the LF turn signal indicator on the dash is illuminated (solid), even when my turn signal switch ISN'T activated. Both filaments on the turn signal bulb are also on at this time, and nothing changes when I flick the turn signal switch. The on-dash indicator was still on even after I removed the flasher for that side. The turn signals on the passenger side work fine!

All my signals work fine (both left and right), when the light switch is NOT pulled out. The indicator turns off as well...

Turn signal switch is new, and I tested with another one just to make sure. The problem socket works fine, too. I tested it on the pass. side. The grounds on all four corners are clean and tight.

My tail lights have stopped working for some reason, too... I am not driving the truck ATM. I'm trying to work out the bugs while I wait for all the parts to my new engine.

Derek.
 
LEB Ben

LEB Ben

Arrogant A-hole At-Large
34,919
1,124
outside your house
Any time I've had feedback like that, it HAS been a ground issue. Tail lights are out, I'd just start working from the rear harness back.
 
smokey

smokey

Hitech hillbilly
Staff member
13,257
706
Garrett Co. Maryland
I agree with Ben on this one.
Salt causes rust making the grounds bad, The sockets have even corroded from the salt out causing the symptoms you experiencing on a few of my trucks and cars.
 
Jolly Green

Jolly Green

I Salt My Ketchup
755
49
Central PA
My vote is for a ground somewhere, too. I know you said you checked them, but there could still be some mysterious ground issue you haven't uncovered yet. This needle in a haystack crap is why I hate electrical!

However, I can see some credence to Doug's suggestion, too. Maybe try a new light switch just to rule that out? If you had a spare laying around it might be worth it.
 

Wbruiser2

68
0
Someone already said it but I would swap the head light switch. There is voltage that runs through it that feeds the instrument panel lights and turn signals. I had a similiar issue: None of my panel lights worked except the left turn signal indicator. I tore it all apart cleaned all the contacts with alcohol and some of them began to work. I took out the headlight switch and cleaned the contacts and all of them work now. I need to replace it though because the slightest turn to dim the lights, they just go off.
 
Fellro

Fellro

Moderator
Staff member
7,953
361
Iowa County, Iowa
I have had clean and tight LOOKING grounds still cause issues. You need to verify that it truly is grounding. I was just fighting that exact issue on my trailer a few weeks ago, and it was the ground. Do the lights totally go out when you step on the brake with the lights on?

BTW, the head light switch ONLY affects one part of the socket, so will not have anything to do with the second filament lighting. That is powered by the turn signal switch. It is impossible for a bad headlight switch to light up the other circuit, just as much as it is impossible for a turn signal switch to light up the marker lamps.
 
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Dirky

1,320
82
Wow, I am an idiot. Everything works perfect now.

Who wants to take a guess??

Hint: No engine in the truck...

Thanks for all the help!!

Derek
 

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