Trailer wiring question
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More Turbo
Joined: May 2018
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From: Butler, OK
Trailer wiring question
Ok, so i am about to rewire my trailer outlets. Double 7 blade, one in the bumper, one in the bed. Im cutting the original harness into a junction box, and putting in a standard 2000 and newer pigtail in for one plug, and doing a double 4 flat setup for the other one...
heres the question, previous owner ran an 8 ga accessory power cable back so the plug could send enough power to matter, to actually charge stuff through.... so, i was thinking id use it, its there. But, having a post mount in the junction box, and me being the special nitwit i am.... id kinda like to hook up the onboard accessory power, too.... am i causing myself any issues, as far as anyone is aware, if i do that?
heres the question, previous owner ran an 8 ga accessory power cable back so the plug could send enough power to matter, to actually charge stuff through.... so, i was thinking id use it, its there. But, having a post mount in the junction box, and me being the special nitwit i am.... id kinda like to hook up the onboard accessory power, too.... am i causing myself any issues, as far as anyone is aware, if i do that?
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Joined: May 2014
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From: Lake Hartwell, GA
Ok, so i am about to rewire my trailer outlets. Double 7 blade, one in the bumper, one in the bed. Im cutting the original harness into a junction box, and putting in a standard 2000 and newer pigtail in for one plug, and doing a double 4 flat setup for the other one...
heres the question, previous owner ran an 8 ga accessory power cable back so the plug could send enough power to matter, to actually charge stuff through.... so, i was thinking id use it, its there. But, having a post mount in the junction box, and me being the special nitwit i am.... id kinda like to hook up the onboard accessory power, too.... am i causing myself any issues, as far as anyone is aware, if i do that?
heres the question, previous owner ran an 8 ga accessory power cable back so the plug could send enough power to matter, to actually charge stuff through.... so, i was thinking id use it, its there. But, having a post mount in the junction box, and me being the special nitwit i am.... id kinda like to hook up the onboard accessory power, too.... am i causing myself any issues, as far as anyone is aware, if i do that?
If I understand you correctly, you simply want to apply 12v accessory power to the 8 gauge wire that the previous owner installed? I don't see any issues with that other than ensuring that your connections and terminals are rated for the amperage you are pushing through the 8 gauge wire to the trailer.
If I am off base on what your intentions are, please disregard my advice and I may take a second shot after being set straight.
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More Turbo
Joined: May 2018
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From: Butler, OK
Um, yes im wanting to reconnect the 8 ga wire. What im wondering about is, if i hook that wire up, in the junction box, will it cause me any issues, if i also hook up the wiring harness accessory wire to that same post, in the box.
Edit to add.... it boils down to, is the onboard harnes key on power, or always on power? Because if its always on, things should work fine. If its key off... then i could be backfeeding power. And possibly causing issues.
Edit to add.... it boils down to, is the onboard harnes key on power, or always on power? Because if its always on, things should work fine. If its key off... then i could be backfeeding power. And possibly causing issues.
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Um, yes im wanting to reconnect the 8 ga wire. What im wondering about is, if i hook that wire up, in the junction box, will it cause me any issues, if i also hook up the wiring harness accessory wire to that same post, in the box.
Edit to add.... it boils down to, is the onboard harnes key on power, or always on power? Because if its always on, things should work fine. If its key off... then i could be backfeeding power. And possibly causing issues.
Edit to add.... it boils down to, is the onboard harnes key on power, or always on power? Because if its always on, things should work fine. If its key off... then i could be backfeeding power. And possibly causing issues.
You can determine the status of your OEM trailer harness orange battery wire using a test light or a meter.
Fleet Owner
Joined: Jun 2004
Posts: 25,090
Likes: 1,112
From: Rio Rico, AZ.
Um, yes im wanting to reconnect the 8 ga wire. What im wondering about is, if i hook that wire up, in the junction box, will it cause me any issues, if i also hook up the wiring harness accessory wire to that same post, in the box.
Edit to add.... it boils down to, is the onboard harnes key on power, or always on power? Because if its always on, things should work fine. If its key off... then i could be backfeeding power. And possibly causing issues.
Edit to add.... it boils down to, is the onboard harnes key on power, or always on power? Because if its always on, things should work fine. If its key off... then i could be backfeeding power. And possibly causing issues.
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Joined: Jan 2005
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From: Henderson, NV
Instead of hooking that 8ga wire direct to the junction box, use a the original trailer charge wire to trigger a heavy-duty relay and then hook the 8ga wire to that. Then connect the other end of the 8ga wire direct to the battery and add a fuse to that 8ga wire circuit.
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Fleet Owner
Joined: Jun 2004
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From: Rio Rico, AZ.
Instead of hooking that 8ga wire direct to the junction box, use a the original trailer charge wire to trigger a heavy-duty relay and then hook the 8ga wire to that. Then connect the other end of the 8ga wire direct to the battery and add a fuse to that 8ga wire circuit.
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Fleet Owner
Joined: Jun 2004
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From: Rio Rico, AZ.
The relay. Use the trigger signal from the factory towing package to operate this relay. Run new power leads from alternator output post to post "30" on the relay, then continue on out on post "87". "87a", from the diagram, looks to me like it would be powered with the ignition off, but would lose power as soon as you turn it on with this particular relay. It's an either/or type of relay. Nothing wrong with it, but I couldn't find just a simple "on/off" relay that was nice and heavy duty like this one.
https://www.ebay.com/itm/203109287396
The circuit breaker.
https://www.ebay.com/itm/273041237337
https://www.ebay.com/itm/203109287396
The circuit breaker.
https://www.ebay.com/itm/273041237337
Thread Starter
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More Turbo
Joined: May 2018
Posts: 729
Likes: 147
From: Butler, OK
The relay. Use the trigger signal from the factory towing package to operate this relay. Run new power leads from alternator output post to post "30" on the relay, then continue on out on post "87". "87a", from the diagram, looks to me like it would be powered with the ignition off, but would lose power as soon as you turn it on with this particular relay. It's an either/or type of relay. Nothing wrong with it, but I couldn't find just a simple "on/off" relay that was nice and heavy duty like this one.
https://www.ebay.com/itm/203109287396
The circuit breaker.
https://www.ebay.com/itm/273041237337
https://www.ebay.com/itm/203109287396
The circuit breaker.
https://www.ebay.com/itm/273041237337
Um... dang bro.... that relay is seriously serious.... i have an anderson outlet in the bed, if i need that kind of power. I think i will go with a regular 30/40 amp relay. The pigtail wires arent heavy enough to handle more than that anyway, i dont think.
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