headlights=no turn signals

[spenser21]

so reading through every turn signal lighting problem, I couldn't find mine. I don't necessarily want to start replacing every switch if I don't have to. as the title says, turn signals work until I turn the headlights on. ive replaced the flasher for the turn signal with no luck there. other then that ive pulled the bulbs for the turn signals and both work, both filaments, just not with headlights on. any ideas?

 

[Georgeb]

What if you only turn the parking lights on by pulling the headlight out one click?

 

[spenser21]

What if you only turn the parking lights on by pulling the headlight out one click?

Sorry I forgot to mention this is on a 74 k10... but on that lol, this is my first K truck so not sure if its right but one click is on lol... hopefully that's right? ive never been able to do just parking lights, its headlights on or headlights off haha

 

[Georgeb]

Well, somebody has monkeyed with the wiring then.....
pick up a Hayes manual at your local auto parts store. they aren't the best out there but they will get you through most of what you need to do. Here is a shot of the left front turn signal and parking light circuit. The right side is mirrored but the wire colors are different. Something is probably wrong regarding how the turn signals are getting their ground. just take your time and study the diagram and the truck a bit.

 

[spenser21]

almost want to just by a whole new harness for the truck lol... im going to be putting in some new led headlights tonight so hopefully I can mess with it some more!

 

[spenser21]

UPDATE!!! not sure if anyone is following this or not but after messing with this for an hour and half I gave up. everything looks to be in order. weird enough after I installed the LED headlights, everything works just as it should. thanks to geroge b who tried to help! definitely got me started in the right direction.

 

[theblindchicken]

huh. that's odd that they worked after swapping the headlights out. I'd check the pinout of your headlights to ensure that it wasn't backwards or anything just in case.

Also, for your headlight switch it should have 3 lateral positions total:

1. (all the way in) - off
2. (halfway) - parking lights on
3. (all the way out) - headlights + parking lights on.

Rotating the switch will adjust the brightness of your dash lights and can manually turn on your dome/courtesy lights.

Floor switch adjusts between high and low beams.

 

[spenser21]

huh. that's odd that they worked after swapping the headlights out. I'd check the pinout of your headlights to ensure that it wasn't backwards or anything just in case.

Also, for your headlight switch it should have 3 lateral positions total:

1. (all the way in) - off
2. (halfway) - parking lights on
3. (all the way out) - headlights + parking lights on.

Rotating the switch will adjust the brightness of your dash lights and can manually turn on your dome/courtesy lights.

Floor switch adjusts between high and low beams.

I did also swap out the headlight switch but ran it a couple days with the stock headlights in and still received the same problem. so I said screw it and just installed the LEDs. just drove it last night for the first time and hit the turn signal out of habit and she works! I tested when I parked the truck and sure enough, all is good.
this is why I hate electrical lol