Hey guys and gals,

I recently traded the ford ranger for a 92' F-250. Description cab be found in my signature. Ive got MAJOR problems. The things that are effected right now are: Headlights (high and low beams), park/turn lights, side marker lights, dash turn indicator lights. Here is what I found


HEADLIGHTS ON
- Pass. Bulb half as bright as drivers bulb
- Right indicator bulb on steady
- Passenger running lights very dim; drivers siderunning lights normal.
- Park brake light on dim

HEADLIGHT ON, RIGHT TURN
- Right indicator bulb dimmer
- Park brake light gets dimmer
- Right headlight, and running lights brighter

HEADLIGHT ON, LEFT TURN
- Nothing happens; everything is like first“HEADLIGHTS ON”

HEADLIGHT ON, HIGH BEAM ON
- Driver bulb brighter (as it should)
- Right indicator in dash and park brake light getbrighter
- Passenger side running lights barley on
- Passenger side headlight stays dim; doesn’tchange

HEDLIGHT ON, HIGHBEAM FLASH
- Right indicator light and brake light on fullbrightness
- Passenger headlight light fades to off
- Passenger side running lights fade to off

"HEADLIGHTS ON" refer to the switch is fully pulled out.
"HIGH BEAMS ON" refer to driving down a country road and the highbeams are fully on
"HIGHBEAMS FLASH" refer to some A**hole has his highbeams on and you want him to turn them off

I checked all the fuses, and they are all good. Any and all help is VERY appreciated, I have no idea where to start.

 

First thing I would check is the grounds.

Seems 99% of issues I have when working on lights is bad or weak grounds.

 

Sounds like you've got a ground problem. Someone will be along with a schematic I'm sure, until then just clean and check the ones you can find.

 

Sorry if this is a necropost but you definitely have signs of a bad ground issue here, unfortunately I can't seem to be able to locate my haynes/chiltons book(s) for these trucks at the moment, but if you wanted I could mail it to you, it covers all F-series trucks of the 87-95/96 heavy duties and don't mind letting another member use it or what ever