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Topic: 12 volts at trailer plug (Read 488 times) previous topic - next topic

12 volts at trailer plug

I had a shop rewire my 7 way trailer plug and have no 12volt hot lead now. I don't remember if it was there from the factory? I use it for my cargo trailer lights on my pickup 7 way.
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: 12 volts at trailer plug

Reply #1 –
There was no 12v on my '99 plug from the factory, I added it myself to charge the Jeep.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: 12 volts at trailer plug

Reply #2 –
I did the same.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: 12 volts at trailer plug

Reply #3 –
Maybe it's there but they moved it's location.
This should be the standard configuration.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: 12 volts at trailer plug

Reply #4 –
The factory didn't have the standard 7 plug from the factory on mine, it was a much smaller round 6 pin.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: 12 volts at trailer plug

Reply #5 –
Quote from: craneman –
The factory didn't have the standard 7 plug from the factory on mine, it was a much smaller round 6 pin.

And per the original schematics, Foretravel did not wire a 12V charge line to the 6 pin when they built the coach, at least not in 2000 or 2003.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: 12 volts at trailer plug

Reply #6 –
A wire from the back of the alternator had been added to my 7 pin with a fuse. Jim.
Jim and Dona
2002 U295 36'
Lily, blue healer. Our fury person
Manx mid travel Ecotec turbo
2022 Bronco badlands Sasquatch
Trail 90 and 110cc

Re: 12 volts at trailer plug

Reply #7 –
The common FT hookup is The selected media item is not currently available.


Our hookup is also missing the 12V tap that we need to add, where have others grabbed the 12V from?  I seem to recall that on our 03 one of the EXTx wires was used from the dash area.

Quote from: fourdayoff –
A wire from the back of the alternator had been added to my 7 pin with a fuse. Jim.
I do like that idea, do you know what value/type of fuse is used?
2000 / 36' / U320 / WTFE
WildEBeest / "Striving to put right what once went wrong"

Re: 12 volts at trailer plug

Reply #8 –
So going to a seven pin connector made sense to me. I added the electric brake controller wire, main battery charge wire and the handy back up wire from the original spare wires ran from the front of the coach. Seems like I recall a 40 amp circuit breaker similar to the other auto CBs for the charge wire. I had to also add the taillight converter because of the trailer light needs. When I was mounting the seven pin receptacle it seemed like a good time to cut and lift the plate for the plug to reduce dragging. Must take in mine the room needed with the door closed. I hadn't given enough clearance and had to actually drop it down a little. While you're up close please take the time to look closely at the trailer hitch receiver. FT could have done a better job welding them on. Look for signs of fatigue. I line of rust next to a weld, paint cracked in a line following the weld, actual visible crack. Probably is fine but a good visual inspection won't hurt. I've also been adding a switch to power up the trailer back up lights to use as work lights. Real handy at times. Adding power to charge the battery from the Alternator makes good sense because it would electricity separate from the coach when shut down.

Re: 12 volts at trailer plug

Reply #9 –
Quote from: steve –
The common FT hookup is The selected media item is not currently available.


Our hookup is also missing the 12V tap that we need to add, where have others grabbed the 12V from?  I seem to recall that on our 03 one of the EXTx wires was used from the dash area.


I do like that idea, do you know what value/type of fuse is used?
Steve looks like 12 gauge with a 30 amp fuse. Has been fine so far. Jim.
Jim and Dona
2002 U295 36'
Lily, blue healer. Our fury person
Manx mid travel Ecotec turbo
2022 Bronco badlands Sasquatch
Trail 90 and 110cc

Re: 12 volts at trailer plug

Reply #10 –
For a toad 12 VDC charge line, two good options:

Direct from chassis  battery with fuse at the battery. This would charge the toad battery anytime the toad is plugged into the coach outlet.

Use a relay if you only want the charge line hot when the coach engine is running.  So, same line from the chassis battery, but use any ignition-hot source in the engine room to close the relay.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020