Lose brake lights when headlights are turned on

[bigtruck]

Alright,,,, so all of my service lights operate normally until i turn my headlights on. Once i turn the headlights on,,, i lose my left turn signal (front and rear) and my brake lights (except the right brake light just stays on,, unaffected by pedal depressing...).. I replaced the headlight switch,,, and it did not correct the problem--- i needed it anyway though,, as the rotating portion of the old one was malfunctioning... I've read the TM's for diagnosis,,, and i'm still in the process of making sense of the F-13/14 wiring schematics.. Just thought this to be a strange relationship between headlights and brakelights/turn-signals,,, but perhaps someone had run into it before,, and could point me in the right direction....? Any advise would be appreciated!

 

[Westech]

ground problem I would bet.

 

[bigtruck]

Any particular ground point in mind that would create my described scenario,,, or shall i just get to checking them all,, and run continuity tests starting at the lights moving toward the switches/power source...?

 

[Westech]

well there is one on the drive side headlight on the radiator support and there should be one on the rear by the tail lights.. I know there are more but thats what i would check to start.. also you can use a jumper wire to ground the lights and see if that helps with out taking the grounds out or messing with them

 

[bigtruck]

Okay, good idea, will do. Appreciate it