Problem With Trailer Running Lights

[Springfield]

Just bought a 2005 that seems well maintained with 193,000 miles. Yes, read about the SMOD but PO had the radiator replaced in 2011 and no signs of contaminated trans fluid or coolant.

It did not have a trailer hitch or connector installed. Bought it to tow a small boat (under 1,000 lb) so bolted on a Curt hitch receiver and got the Curt custom 4-wire cable that plugs into OEM plug near drivers rear leaf spring (part # 55441). Trailer lights work good except for NO running light. Digital voltmeter shows only 4.5 volts when parking lights turned on. Check back on vehicle at OEM connector - contacts are all bright copper but still only 4.5 volts on running lights pin.

Been looking thru forums and searching, found posts mentioning relays behind passenger kick panel - popped off the panel below dash in front of passenger side door but didn't see any relays ...

I can always re-wire the trailer running lights to come from the rear bumper license plate lights, but would rather fix the root problem if I can.

Any ideas?

Thanks!
-Ken in FL

 

[Brunnie]

If no relays, then you need some. I do not have the part numbers off hand, and there is a wiring harness that goes in there as well.

Now the relays may be in that bundle someplace, especially if you see something wrapped in foam.

 

[TerryD]

You'll need the proper harness with the relays.

I have a set in my basement I think. It's an aftermarket kit that's plug and play.

If you're interested let me know, I'll make you a good deal. It worked but I went with the Nissan one in the end because I wanted the accessory wire and brakes with the 7 pin.

 

[Springfield]

You'll need the proper harness with the relays.

I have a set in my basement I think. It's an aftermarket kit that's plug and play.

If you're interested let me know, I'll make you a good deal. It worked but I went with the Nissan one in the end because I wanted the accessory wire and brakes with the 7 pin.

Thanks, Terry. I'd be interested if you can find the aftermarket kit, new they are running like $40-55.

As I mentioned in the other thread on electrical schematics, installing just the 4-wire pigtail to the rear OEM connector gets proper brake and turn signals on the trailer, so there must be a converter already built-in somewhere.

Being a cheap guy, I'm wondering what is the advantage of the relay kit if simply connecting the trailer light feed to the license plate light will get things working?

 

[Brunnie]

Being a cheap guy, I'm wondering what is the advantage of the relay kit if simply connecting the trailer light feed to the license plate light will get things working?

You summed it all up right there..... IMHO.... that is going to bite you right in the butt. You can pay now or you can pay more later, your choice.

 

[TerryD]

Thanks, Terry. I'd be interested if you can find the aftermarket kit, new they are running like $40-55.

As I mentioned in the other thread on electrical schematics, installing just the 4-wire pigtail to the rear OEM connector gets proper brake and turn signals on the trailer, so there must be a converter already built-in somewhere.

Being a cheap guy, I'm wondering what is the advantage of the relay kit if simply connecting the trailer light feed to the license plate light will get things working?

I'll look for it tomorrow.

The advantage is that the trailer has its own feed so if you short or a trailer light you don't lose the truck's lights.