Parking lights do not turn off

Hi,

I attached the wiring schematic below for the exterior lighting. It appears that power for the parking lights is provided by fuse 17 in the interior fuse panel (left side under dash). From there power goes to the switch and is distributed to all parking lights via brown wires.

Do the lights stay on when the fuse (17) is removed? Also, fuse 7 in the same panel is for the automatic light control. What happens if that is removed?

Let me know.

Take care,

Joe

See pics below. Note: There were two pics. I had to cut them in half to make them readable for you. I did overlap them so you can follow from one to the next. Pics 1/2 and pics 3/4 are from the same pics. The last pic is the central junction box I mentioned with the fuses highlighted.

If they turn off when that fuse is removed, then there isn't a short to power which I suspected. It sounds like the switch itself is bad. By chance, have you replaced it?

Let me know.

Joe

Hi,

Fuse 17 powers the headlamp switch and 7 powers the multi-function switch. Does one turn off the parking lights? If fuse 7 turns it off, then I suspect there is a short at the multi-function switch. If 17 turns it off, then it has to be at the switch.

Also, does this truck have DRL (daytime running lights)?

Let me know.

Joe

See pic below.

Hi,

I looked up parts and labor to find the part number. You indicated it has fog lights. The headlamp switch w/ fog lights is different between with DRL's or without DRL's. Both appear to have a 9-pin connector.

See pic below for OEM part numbers.

Joe

See pic.

Alex, the only way to determine if the fuse box is correct is to locate the part number on it. It should be scribed in the plastic near the bottom, but not easy to find.

As far as the switch is concerned, it can have fog lights with either with DRL's or without DRL's. Just refer to the part numbers I didn't highlight.

Also, if you can, take a pic of the fuse box so I can see it. I can try to make a few comparisons for you. Also, here is a link where you can put the truck's VIN number in, and it will help decode what the vehicle came with. With GM and Chrysler, they have RPO numbers that are very specific. I don't think Ford is the same. But if it is, there should be a label in the glove box that looks similar to the pic I attached below. I found that example online. You can check under the hood as well for the label.

https://www.ford-trucks.com/forums/vindecoder.php

Take care of yourself and let me know what I can do to help.

Take care,

Joe

Hi,

I have a feeling the switch is the wrong one for the system. At this point, we don't know exactly what we are dealing with. However, we will figure it out.

Take care and I'll watch for your reply.

Joe

Hi,

This gets more and more confusing. By chance, did you determine if the fuse box is the original one? Did you try pulling the trailer tow parking lamp relay?

Let's look at this from a different angle. This may sound crazy but remove all the parking bulbs that stay on. With them all removed, check which ones have power and which don't. Maybe by doing that, it will help us narrow things down.

Or go to the headlamp switch and locate the brown wire. Is there power to it at all times? If there is, disconnect the switch and see if the power stops at that wire.

Let me know.

Joe

Hi,

With the switch connected and off, do you have power on both brown wires? You shouldn't. The tan wire with the white tracer is power in from fuse 17. The switch should cut power out to the brown. See pic below.

Also, I noticed there is duct tape on the connector. Are you certain nothing is shorting between wires due to a bad connector?

Let me know. Why they would use the same color in the same connector is beyond my knowledge. Anything to make it more difficult. LOL

Look at the pic below.

Joe

Hi,

I went back through the schematics. The only power supply to the switch is the tan wire with a white tracer. The brown wires get power with the switch on but shouldn't with it off.

Take a look below. That is what I'm seeing as the connector. If you read through each pin's circuit function, note that pin 10 is the aforementioned wire and it is the power supply.

Take a look through the circuit functions and then check the pins to see if they are accurate. Note: the connector only shows two solid brown wires. One is power out from the switch to exterior lights and the other is for fog lights.

Let me know where the third one goes to in the connector. (Pin number)

Joe

See pic below.