Trailer and shell wiring Problem
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Trailer and shell wiring Problem
I have an 02 Super Crew, When I bought it it did not have a tow hitch or wiring. I had that put on shortly there after to pull my trailer. I just discovered that there is no battery voltage to charge my trailer batteries. Should there be a constant 12 volts on the in the plug along with the battery charge circuite?
Also I just had a shell put on my truck and I am looking where to hook into the brake lights to run the third light above the shell door. Also I need to tap into a constant 12v to run the interior light. Any suggestions?
Also I just had a shell put on my truck and I am looking where to hook into the brake lights to run the third light above the shell door. Also I need to tap into a constant 12v to run the interior light. Any suggestions?
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From: DIXIE
Did you install the 6 pin round style plug for the trailer or just the 4 pin pigtail? The 4 pin pigtail has no 12vdc constant. As for the cap, you can just run their wiring to the brake light socket on the back of the cab. That will trigger the cab light when you turn on the bed light or you can run it to a constant 12 v in the overhead light. I would use a plug though so that its easy to remove.
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Joined: Jul 2005
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the 7 pin harness stops on the left frame rail across from the spare tire. from there, you get nothing or a 4 pin connecter to the liscence plate area, unless you order the "towing package" which they then install the bigger harness with the "red" wire that is hot. they also remove the relay up front under hood that puts big amps to the back end for charging batteries. when you get the factory "big" harness you also get the relay. if aftermarket installed, they probably left off the red wire, and / or the front relay.
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From: Panama City, Fl
On my '01 F150, I did not have the factory tow package.It had the small 4 pin plug. I installed the 7 pin unit. I did find the hot wire stopped near the spare on the right side and there was another wire that ended there also. They both ended at a plug. I could not find pins to make the connection so I just jumpered around the plug and soldered it with shrink tubing. Also, got the relays and plugged them in. On a side note for the trailer battery charging, my car hauler uses the tail light wiring to charge the battery. The company said that the small battery on the trailer may not always like the constant charge. So far, mine has worked great. I also have some work lights wired to the trailer battery.
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I bought the relay for under the hood so I now have the 12V to charge the batteries. It is nice to know I have been pulling my trailer around for two years without charging the batteries.
I have yet to find the red power wire, I will look again at the plug by the spar tire. Do you know which wire to hook to the brake light on the shell? I thought I had it until I turned on the right signal and the light flashed.
I felt like the little this little dude. Is there a brake power only in the plug by the spare to hook the brake light on so it won't flash with signals?
I have yet to find the red power wire, I will look again at the plug by the spar tire. Do you know which wire to hook to the brake light on the shell? I thought I had it until I turned on the right signal and the light flashed. I felt like the little this little dude. Is there a brake power only in the plug by the spare to hook the brake light on so it won't flash with signals?
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From: Panama City, Fl
All brake wires at the rear of the truck should flash with the turn signals. The one "brake only" wire is the one going to the third brake light on the cab. This is where you get the power for the shell brake light. I believe this is all accessed from under the headliner or thru removing the third brake light from the cab. Not sure where the wire runs inside the cab.
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Well folks, just an update. I finally ran a fused wire from the battery to power the interior lights on the shell. To get the third brake light to work I finally took all the wires out of the loom and found a single wire that just dead ended in the wire loom with shrink tube on it. I probe it with my test light and found it worked with brake pedal, So I attached the third brake light to it and viola, fixed.