trailer tow relay

[zpd307]

i recently had to replace the headlight switch. i also had to to splice in a new connector as the original had melted. anyway, i am going to do the relay mod for the headlights and found some are doing the relay mod for the trailer taillights also. while rooting around in the engine compartment, i found a relay on the driver side fender marked trailer tow. its right next to the vacuum canister. i tested it and found that turning on the headlights activated it. so, my question is when did ford use the relay, maybe the mod was for older fords, and should i still do the taillight relay mod.

[macmaniac1]

I don't really know the years on this relay. I have to replace my headlight switch, dimmer switch, and that trailer tow relay on my 91 f-350 over the years.

[M.L.S.C.]

Got a factory tow package? My truck is factory tow (with wiring for controller and also color-matched for a 7-way connector as well), I got a relay right in the area where you say, I'm gonna look at it tonight, but it may very well be for the trailer wiring.

[zpd307]

from what i am seeing, the truck does have the factory tow wiring. the wiring to the controller looks factory. it goes through the firewall, then it splits off and part of it goes to the relay. it is all wrapped up into the factory harness. i do not see any fuses for this wiring.