Fordrocks689

Hey everyone I need some help here I'm stuck.

99 F150 4.6l 2wd

My passenger side reverse light isn't working. The driver side comes on just fine. Everything els in the truck works great. When I first got the truck it wasn't working, I took it apart changed the bulb and still nothing, then I flicked it with my finger and walla it came on. I put everything back together and bam , it still didn't work. I took it apart again and when I flicked it this time it barely flashed a little and then nothing. So I thought it was the light bulb socket. I went and got a new one and spliced it in and still nothing.

It's only the passenger side it doesn't seem to get any power... the brake light still works.

What I've done...

I've checked all the fuses under the hood and under the driver side steering wheel. I've used multiple bulbs and even wired in two different sockets.
I double checked that I wired it correctly they are color coded clearly so I know i spliced it right....


Can anyone help???? Thank you

cmgoldn

After you replace the lightbulb, do you then close your tailgate? This might create enough vibration to render the bulb inoperable. Are you using regular 194 bulbs or are you using LED 194s? Is the passenger side wire harness the main lead or is it spliced from the main lead? Did you chase the wires all the way back to the main bundle and check for worn insulation?

Fordrocks689

No I left the tailgate open, I actually pulled the wires out through the bottom so I could splice it correctly so it was just hanging the whole time un touched. I did chase it back and it looks like the passenger side is the spliced line as it follows leads back to the driver side. I did shake off the dirt from the harness and checked for any damage and did not see any. Where I did find damage was at the trailer tow plug right were it goes into the harness it was damaged and 3 out of the 4 wires were exposed. I separated them all and double checked all fuses again. Still nothing , I'm not even sure if the tow harness caused a short it's just something I found while under there. And they are regular bulbs not led

Fordrocks689

The brake light follows the same line as the reverse light and the passenger brake light works just fine. Could it still be the insulation?

cmgoldn

It sounds like you had a connection when you initially replaced the bulb and the bulb connector (not sure if that's what it's actually called). I would not rule out bad insulation at this point because it worked after you replaced it. After you replaced the bulb and bulb connector, did the bulb filament burn out or is it still in tact?

cmgoldn

I'm sure you checked the manual to determine what's all on that circuit, the circuit that controls the reverse lights in addition to everything else on it. I would check each bulb on that circuit to verify they are the proper bulbs, then check the wire all the way up to its main bundle. After that, I'd check the existing bulb you replaced and the new bulb connector/receptical. I know it's new, but sometimes new parts can be defective. If the pass side is a splice off the drivers (main) side you have a pretty short run to troubleshoot. I'd pay close attention to the trailer hook up too, I've had similar problems where the trailer hook up was wrapped around the top of the bumper/frame bracket and simply was worn thru and shorted out my parking lights.

Fordrocks689

Yea tomorrow I'm going to just pull all the wire out and check it all up the main splice. That's the only thing I can think of at this point. It was weird because the first time I flicked it , it came on full brightness but it seemed like every time after that it got dimmer and dimmer until nothing. And yes I made sure to check that every light I was using was still intact. I even swapped them with the other side.

Fordrocks689

Worst comes to worst could I just run and new ground and 12v from the driver side light?

Fordrocks689

Oh and the license plate lights are on that line as well and those are working too just FYI

cmgoldn

Ok, sounds like you've checked everything. I have to say it sounds like it's probably a connection at the factory splice. I'd open the factory splice to see if the connection is corroded faulty before running a new ground.