1990 Ford F150 Pickup, No Headlights

This 1990 Ford F150 Pickup came in with a complaint of the headlights work sometimes and sometimes they do not.

The easiest place to start is at the headlight switch on this truck. the first step is to remove the headlight and wiper switch knobs. There is a slot in each one of the in which you have to depress the metal spring latch and pull the knob from the shafts.

With the switch knobs removed I next removed the lower dash cover. It is held in place by four plastic zeus type twist locks. This one had the electric brake controller attached so I just let it hang in place rather than disconnecting the wires.

Next I grasped the trim panel and pulled it towards the seat until it unsnapped and released.

I had some more things to repair on this truck so I went ahead and removed the trim panel on the right side of the steering column. There is one screw that is hidden under the left panel and then it pulls off just like the other. After that I removed the three of four screws that hold the switch plate in place.

I pulled the switches out and this is what I found. The Red/Yellow wire which is the power supply out to the dimmer switch and then to the headlights was burnt.

Time to install a new Motorcraft headlight switch SW6352 and The Electric Connection repair harness #4000 . To order this repair harness please click here. Next I had to remove the nut that retains the switch to the mounting plate.

With the nut removed I pulled the switch from the mounting bracket. I then flipped the switch over to reveal the release button for the pull handle shaft.

I pulled the shaft out until it reached its stop and then pushed in the retaining button and finished pulling the shaft from the switch.

The next step was to release the retaining ears on the harness connector. I had to pry them away from the switch while pulling the harness connector in a rocking motion to fully release the connector from the switch.

The connector looked even worse from the switch side.

I started switching the good old wires from the original connector to their corresponding locations in the new connector. The terminal locks can be released with a paper clip, small screw driver or a terminal tool. I then cut the remaining wires from the old connector.

Once the old connector was out of the way I could pull and adjust the wire length to the proper position for the wire to lay flat in the harness.

After cutting the new and old wires to length I cut and additional 1/4 inch from the longer wire. This makes up for the extra length that comes into the wiring when the splicing connector is installed.

After the terminal and heatshrink tubing was in place I proceeded to splice the remaining two wires. The wires had not been damaged but it is so common for the park light wires to burn out in this type of system I decided to go ahead and do some preventative maintenance for the customer.

I also staggered the spliced joints so that the harness would not have a large knot in it that could cause other problems.

I taped the harness back up and reassembled the dash.

On to the next problem.