Hey folks, my 2002 Excursion, V10 model is giving me some grief on trailer lights.
Using the factory round plug, I am getting brake and turn signals, but not the running lights and parking lights. Also, the circuit that controls the reverse solenoid is not working so hard to backup as well.

I have checked all fuses and did some research online. Seems lots of different trucks and years are different in some aspects, whether diesel or gas or even in years. So confused.

Thinking the issue might be a solenoid as I understand there are different one's for each circuit. Question is where are they?

The manual is not clear and does not break down the individual solenoids and location.
Some folks say they are under the hood, some say is under the dash near/under radio and between steering column, etc.

Anyone out there actually know?

I do not have any fuses under the hood. Seems all are in the one large one just under the steering column behind the removable panel. This is where I checked and using a voltage meter, checked circuits to all fuses and all were working.

Perplexed on where the solenoids might be, and then, where to get them as not finding anything like the description for trailer light solenoid on several of the parts stores online. Maybe a ford only item?

 

Fuse # 4 under the hood, controls trailer parking and backup lamps. The box is located on the drivers side fender near the brake master cylinder.

Not sure what you are referring to when you say the reverse solenoid??

 

Sorry, on my trailer, there is a reverse solenoid that is activated by the reverse light signal. That was not working which meant no juice going to that circuit.

As mentioned, there are no fused or fuse boxes under the hood. I found a reference in the haynes manual that it was changed for 2002 model.

I revisited a copy of the 2002 manual I had at home after returning from my trip and this copy was more clear than the one in the glovebox. Maybe had the wrong one, dunno, but it shows the following:
Fuse/Relay Loc./Fuse Amp Rating/Passenger Compartment Fuse Panel Description
6 20A* Trailer tow turn/stop relay
38 20A* Trailer tow park lamps and backup lamps

So number 6 and number 38 to test.

I rechecked number 6 and it was good.
I rechecked number 38 and it was blown!

Pretty sure it was not blown when I was down at the coast and checking it, but with all that sweat dripping into my eyes, maybe I was blinded!

I replaced the fuse and checked output on the round connector and circuits for both the reverse and park lights is working now.

I won't know until I reconnect in a couple of weeks, if this is resolved or not.

My trailer has new wiring from last year and I did a spot check on it and did not find any issues where I might have a short.

We will see in a couple of weeks. Under the hood, on the drivers fender near master cylinder are two relays that might be for the trailer harness, but will reserve need to investigate this after I find out if it was just this fuse.

 

He has an 02, not a 00. Everything is different, there is no under-hood fuse panel on an 02 and later SD chassis.

There are no solenoids in this circuit in the truck, it uses relays. It's pretty hard to find something that doesn't exist.

Check fuse F38, it supplies operating power for both the running and backup lamp circuits for the trailer adapter. If the fuse is supplying power as required, then you may have failed relays for each of those functions. The relays are not easily serviced as they are soldered to the main board in the central junction box (CJB). A skilled electronics tech can replace the relays, otherwise, the repair requires either replacing the whole CJB or scabbing an external relay around the failed part.

[Edit] I see we were both posting at nearly the same time.

Those two relays are for the trailer turn/brake signals.

 

Learned something right there, sorry about the bad advice. Same fuse,wrong location.

 

Yeah, there was a complete electrical system redesign that was implemented for the 02 model year.