Been working on vehicles since the 70's finally came on something that has me stumped. Pulled old 2000 ram out of barn for son to use and seem to have head light issue. Started out as low beam light driver side would not come on, tested and replaced all fuses, looked for any obvious corrosion or broken lines and found none. Also checked wiring in steering column and found no issues. Move around cable harness to see if this would a reaction. NOPE. Just out of curiosity turned lights on and pulled fuse for right side headlights out. WTF. All of a sudden all four lights came on including right side which has no fuse in holder. Before this tested line for left side low beam and had no reading on meter and the continuity tester showed nothing. Bulb in tester is working tested it on right side lights and battery. Also checked light switch. Wire for low beam is violet with white tracer line. I am stumped folks any ideas would be appreciated.

 

Is that a sport model by any chance? (four headlight system)

You can download a copy of the service manual from here. Wiring diagrams are in section 8W.

 

Sport model quad cab 5.9 360

 

Looks like the headlamps should have constant power, and ground side is controlled by a switch. Diagrams are a bit confusing...... In any event, the Pink/Red wire should be constant 12 volts.

 

should be no power when fuse for right side is pulled, but all 4 come on. Driver side and passenger side low and high beam

 

From what I am seeing, Fuse E in the PDC powers all the headlights.......

 

If just low beam isn't working, just put in a new bulb. This just happened to me on my road trip at night in Montana. Low beam driver's stopped working and grabbed some new bulbs in Billings. Easy peasy.

 

My problem was the multifunctional switch. The contacts actually inside of it were corroded and I took it apart and cleaned them

 

Thanks for adding your final findings, it helps.

 

What happened to me was the headlights were working. Parked the truck for 10 mins came out no headlights. Turned it to be the multifunctional switch. Now my headlight switch is bad