The low beam headlights of my 1999 Expedition do not work. The high beam headlights work. The multifunction switch is working correctly. I have traced the wiring for the low and high beam to the fuse block. The high beam wiring is noted correctly on my schematic. For the low beam, the schematic shows one red/yellow wire from the head light switch and one red/blk wire from the multifunction switch to fuses 26 and 28. In actuality, there are two red/yellow wires, but no red/blk wire. One red/yellow is from the headlight switch, and the other works as the red/blk on the schematic shows. Finally, there is a red/blk wire that goes to the fuse block in the correct location for the fuses. Where is this transition made?
Year : 1999Make : FordModel: ExpeditionEngine: 4.6L V8 W
Below are the Ford wiring diagrams.
The wiring goes from the multifunction switch to the bulk connectors sending the power outside to the Day Time Running Lights relay block if you have it and then back inside the vehicle to the fuse box. That is where the transition is made in the wiring color. The day time running light relay block is located behind the dash on the passenger side. There should be a panel on top of the dash which is kind of oval that pulls up. It is clipped to the top of the dash.
Make sure you have power at the relay block with the low beams turned on.
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