I have a 1990 pickup with the 3.0. I changed all the exterior lights to led and now when I use the turn signals, all 4 blinkers flash as if I turned on the Hazzards. Can't figure out what's going on. Any help?

 

It sorta begs the question, if you put the old bulbs back in do the turn signals work properly?

 

I haven't put the original bulbs back in nor do I have them anymore. The bed is gone and the headlights were changed to led with built in turn signals. I did have to buy a stand alone harness to get the headlights to work properly, is there some sort of connection that has to be made for the turn signals to work. The hazards work fine, just the turn signals act like you turned the hazards on.

 

Here:
https://www.yotatech.com/forums/f116...issues-254754/

 

So you took the original turn signals out and now are using the built in signals in the headlight housing and had to get a different harness for the headlights to work? Was the original turn signal wiring tapped into the new headlights? Besides the hyper flash issue if you have it, it sounds like something is crossed, led bulb bad, wiring needs to be looked at etc, very hard to troubleshoot when aftermarket headlights with stand alone harnesses are wired, we have no clue what has been done here…..

I would trace backwards from when they worked and go forward from there.

 

Thank you, you made my day. I am also having the same issue.