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My running lights are stuck on. I read another thread on a different forum about the same problem, and the guy pulled his #4 relay under the hood, and the running lights shut off. The same thing happened with my truck. The guy never said what he did to fix it in the end. The relay is for "trailer tow lamps." Thoughts?
The trailer wiring is all a mess. I had to rewire all of it, and I still don't have the trailer system wired back up. There isn't a pig tail back there anymore.
I have no idea if I have a keyless entry. Also, I got everything rewired. I have a 7 pin trailer plug back there and no more loose wires. However, after playing with everything, I still have the same problem. But everything works perfectly with the number 4 relay out. Would it be ok to just leave it out?
The number 4 relay is for the trailer tow lamps. I pulled it out and didn't replace it. Everything works as it should. All the light work on trailers, all the lights work on the truck. Can I keep it like that or do I need to fix it?
Check voltage/continuity at the relay receptacle. If you get voltage across the load side of the relay receptacle, you have a backfeed. Or, if you have continuity between the line side and load side on the relay receptacle, then you also likely have backfeed. Is there an additional 7 pin in your truck bed?
30 - yellow, constant hot
87 - brown/white, 12V out to lamps
86 - black, ground
85 - brown, switched 12V into relay, from main headlight switch
It is probably something very simple. Do you know if you have an old alarm or keyless entry system? It is well known the main headlight switches in these can fail and have melted wiring.
Everything is wired as it should be. However, I don't know about the keyless system or alarm. Where do I look for these?
I put my keyless module behind the passenger kickpanel. You may want to check the driver side too and under dash by column. Often times folks want their lights to flash to confirm locking or unlocking. My F-150 had some clapped Viper alarm system wire tapped into everything.