Electrical Crap
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Freshman User
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Electrical Crap
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?
Lead Driver
Joined: Sep 2002
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From: North Texas
How did you rewire it? There should be a four wire pigtail and a three wire back there. Nothing to it.
Your interior switch could also be damaged. The power feed to headlights runs through it on a stock assembly.
Your interior switch could also be damaged. The power feed to headlights runs through it on a stock assembly.
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Freshman User
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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?
Lead Driver
Joined: Sep 2002
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From: North Texas
Swapped relays?
What is the switched 12V trigger source for R4? Or tell me what R4 is and I can look.
What is the switched 12V trigger source for R4? Or tell me what R4 is and I can look.
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Freshman User
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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?
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Brett Foote
Mountain Pass
Joined: May 2017
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From: Colorado
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?
Lead Driver
Joined: Sep 2002
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From: North Texas
Yes, I would fix it correctly.
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.
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.
Lead Driver
Joined: Sep 2002
Posts: 9,554
Likes: 2,035
From: North Texas
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.
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