Trailer lights and headlight switch--confused...

[Mikes91]

Now that I have the new headlight switch/pigtail installed per Magoo's method, things are running nice and cool behind the dash with all the lights I have on the truck (stock, plus 2 small bulbs in the marker poles). I can hold the pigtail wiring loom in my hand and it doesn't get the slightest bit warm, even with the brights on.

I suspect that the meltdown of the pigtail was related to pulling a couple of trailers with lots of lights, but thought that those lights were run through another circuit and NOT through the headlight switch. ?? Or was it that they are possibly wired incorrectly and ARE being run through the headlight switch?

I don't see any wiring harness for trailers tucked away anywhere on my truck. I'll doublecheck when there's light outside (I'm always at school during daylight hours). Just want to resolve my confusion on this and get things wired right so that I can avoid having to replace the pigtail again.


Thank you,

Mike

 

[Agnem]

Mike, if you got a trailer towing package, then you should have a relay for the trailer lights. If no trailer towing package, then you're probably running through the switch.

 

[MIDNIGHT RIDER]

Easy to figure.

If the trailer lights come on with the truck lights, then trailer lights are getting current from truck-light system.

I would bet dinner that the trailer lights are spliced into the tail-light wire somewhere under the truck bed.

 

[Mikes91]

Easy to figure.

If the trailer lights come on with the truck lights, then trailer lights are getting current from truck-light system.

I would bet dinner that the trailer lights are spliced into the tail-light wire somewhere under the truck bed.

Thanks guys. I'm fairly certain I'm running through the switch, then (explains the burnup rather nicely since I've verified things stay cool when no trailer is connected). After poking around last night, I can't find anything that would lead me to believe the truck had a trailer tow package installed. No special stuff in the relay box under the hood.

Reading through the old posts regarding trailer lights... it looks to me that the advice given is to run trailer lights through a separate switch, 20A fused. OR, would the parking light relay mod be another route I could take? Trailer lights seem to key off the parking light circuit, so it seems to me that relaying the parking light circuit SHOULD effectively get the trailer light load off the headlight switch. I'd imagine that it isn't quite as robust as the separate switch for the whole shooting match.

How are turn signals handled?? Through the turn signal relay? I assume it handles that load satisfactorily... What about brake lights? Just thinking out loud after a shot of caffeine and a busy morning of thinking too hard about serious stuff...


Thank you,

Mike

 

[deanj]

Do the running lite relay mod, it will take the load off the switch. Most of the problems with the switch failing are due to the running lites.

 

[Mikes91]

Do the running lite relay mod, it will take the load off the switch. Most of the problems with the switch failing are due to the running lites.

Thank you... can't wait to get that done.

Now, what would be the best place to tie in the trailer light wires? I assume the current location is fine once the relay mod has been done.