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Topic: trailer plug (Read 444 times) previous topic - next topic

trailer plug

does ant one know where the 12vdc comes from to charge the battery on a trailer the pin for 12vdc has a wire on it but find no information in book on 7 pin plugs for this wire it red which is good but need to find out where it hookup to now I have no power on it
brian eichhorn
2001 u20 34'

Re: trailer plug

Reply #1 –
Very likely not OE from the factory. Likely you will have to trace the wire.

It should go to the chassis battery or place connected by large-gauge cable to the chassis battery AND should have an in-line fuse at the connection to the battery/other "place".

Also  need a fuse at the toad battery end.
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

Re: trailer plug

Reply #2 –
WIRE GOES LEFT AROUND ENGINE COMPARTMENT THEN INTO WIRELOOM  BATTERY IS ON RIGHT SIDE NOT LEFT WILL LOOK FURTHER
brian eichhorn
2001 u20 34'

Re: trailer plug

Reply #3 –
If in doubt and you do not have a wiring diagram showing that it is done properly (with fuse and at least 10 gauge wire) REDO IT.
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

Re: trailer plug

Reply #4 –
Quote from: bvectra –
does ant one know where the 12vdc comes from to charge the battery on a trailer the pin for 12vdc has a wire on it but find no information in book on 7 pin plugs for this wire it red which is good but need to find out where it hookup to now I have no power on it

As Brett says, this is not standard/OEM wiring and would have been added by/for a previous owner who requested a charge line be run.
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: trailer plug

Reply #5 –
Not sure what coach you have. You might want to add the info to your avatar.

What Brett said will work fine. You might check the number on the wire, if it reads extra #XX, it may be disconnected at the front. It was normal to use one of the extra wires for a charge wire. You will find it exiting at the left front of the dash.

On our 97 U 295, I torched out the hole for the plug larger. Installed a seven round plug. Used one of the extra wires in the harness to the front. Added a 20 amp breaker.

I run mine off an ignition source from the electrical junction at the right front of the dash.
I also used an extra wire for trailer brake control, and activation light on my dash for my aux toad brake.
Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348