Trailer lights question
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Resident smarta$$
Joined: Aug 2006
Posts: 4,929
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From: Oaks,PA
Trailer lights question
Quick towing question, I used my 7-pin for the first time Friday night to tow my buddies Bri-Mar dump trailer to get some firewood from where I'm working. 4 ways worked, couldn't check brake lights since I was by myself, but it is a newer trailer in good shape and he is not one to slack on PM or let his stuff turn to crap so I trust the issue is with my truck. On the way home, closer to dark, I see the marker lights arent working on the fenders. Got home, dumped the logs and the parking lights weren't on either. I called him and he thinks there is a fuse I need to install or check but my manual says nothing about installing a fuse anywhere I can see so the trailer lights work with a 7-pin connector.
The battery charged, the turn signals worked, any suggestions? Thanks in advance, I have to take it back later today. I will post pics as soon as I size them
The battery charged, the turn signals worked, any suggestions? Thanks in advance, I have to take it back later today. I will post pics as soon as I size them
Postmaster
Joined: Oct 2004
Posts: 4,155
Likes: 0
From: Southern Louisiana
There is a fuse that you need to install. As said above, in your glove box there is a plastic package with the fuse, brake controller pigtail and the instructions on where the fuse goes.
Elder User
Joined: Nov 2008
Posts: 668
Likes: 6
From: Northfield, MI
The fuse and relay that are supplied loose are for the battery charging circuit and nothing else. Seriously, this comes up like every week.
If your running lights aren't working then you need to check the fuse. If the fuse is good, then you will have to check out the wiring. If the fuse is blown there is a 99.9% chance the trailer wiring is bad.
Don't overcomplicate this.
If your running lights aren't working then you need to check the fuse. If the fuse is good, then you will have to check out the wiring. If the fuse is blown there is a 99.9% chance the trailer wiring is bad.
Don't overcomplicate this.
Thread Starter
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Resident smarta$$
Joined: Aug 2006
Posts: 4,929
Likes: 9
From: Oaks,PA
The fuse and relay that are supplied loose are for the battery charging circuit and nothing else. Seriously, this comes up like every week.
If your running lights aren't working then you need to check the fuse. If the fuse is good, then you will have to check out the wiring. If the fuse is blown there is a 99.9% chance the trailer wiring is bad.
Don't overcomplicate this.
If your running lights aren't working then you need to check the fuse. If the fuse is good, then you will have to check out the wiring. If the fuse is blown there is a 99.9% chance the trailer wiring is bad.
Don't overcomplicate this.
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Resident smarta$$
Joined: Aug 2006
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From: Oaks,PA
OK I put the hi power black in #9 trailer tow battery charger. Maybe the battery for the dump trailer was still charged, he thought from sitting it might be dead. I put the 30A in #21 trailer tow battery charge. I will have to hook up the trailer again some night this week to see what the lights are doing. With all that said, I guess if the lights still don't work I can swap #6 (trailer tow park lamp relay) and 9 and see if that's the culprit, then go from there. Thanks guys
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OK I put the hi power black in #9 trailer tow battery charger. Maybe the battery for the dump trailer was still charged, he thought from sitting it might be dead. I put the 30A in #21 trailer tow battery charge. I will have to hook up the trailer again some night this week to see what the lights are doing. With all that said, I guess if the lights still don't work I can swap #6 (trailer tow park lamp relay) and 9 and see if that's the culprit, then go from there. Thanks guys
bobo06
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Resident smarta$$
Joined: Aug 2006
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From: Oaks,PA
FireMe, I was thinking about what you said regarding the trailer wiring. I figure it has to be my father-in-laws trailer with the cobbled together wiring that blew the fuse. I use that sometimes to tow my mower. I will see next time I hook up to it. Thanks again for all the replies
Logistics Pro
Joined: Oct 2004
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From: FL
Should have no issue using the mini fuse vs the low profile one. As long as you used the correct amps, which it looks like you did.
Elder User
Joined: Nov 2008
Posts: 668
Likes: 6
From: Northfield, MI
FireMe, I was thinking about what you said regarding the trailer wiring. I figure it has to be my father-in-laws trailer with the cobbled together wiring that blew the fuse. I use that sometimes to tow my mower. I will see next time I hook up to it. Thanks again for all the replies
Yes, I hate when other people borrow my truck to pull their trailer around as I usually get it back with blown fuses, kind of the opposite of your situation.
Very few trailers seem to make it more than a few years before wiring issues set in either due to cheap workmanship or damage.
Always carry a handful of fuses for the trailer circuits, and yes as stated above you can substitute the tall minis for the short minis as long as the fuse fully engages the terminals. I've seen fuses that didn't make good contact and this results in high resistance and heat damage to the fuse box.
