How to Wire 12V Auxiliary Power Circuit in 7-Way RV Wiring
Updated 04/03/2018 | Published 04/01/2018
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Question:
Have the Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps Item # C57674 hooked up as your video explains for a 2015 Subaru Outback. I have a small tear trailer I built and would like to provide power to charge the battery while towing. Would you happen to know where I would pull power from to supply 12v through the 7 pin connector to use for charging the 12v trailer battery while towing?
asked by: Troy B
Expert Reply:
On standard 7-way RV-type trailer wiring the contact at the 1:00 position as you view the socket carries the 12V auxiliary power circuit that can be used to maintain a trailer-mounted battery as you travel. Please refer to the linked photo.
Note that this charge is enough to maintain a charged battery while you drive but it does not deliver enough power to re-charge a depleted battery. For re-charging a depleted trailer battery you really need a shore-power AC charger like the NOCO # 329-GEN1 which works to charge lead acid batteries up to a 230-amp-hour rating.
On the Curt 4 Pole to 7 Pole Adapter # C57674 this contact is fed by the black pigtail lead. This wire should connect to the battery + terminal through a 40-amp auto-reset circuit breaker like # PK54540 using 10-gauge wire like # 10-1-1 and ring terminals like # 44-5310A.
I have attached diagrams of the 7-way plug wiring pin out.
Product Page this Question was Asked From
Adapter 4 Pole to 7 Pole and 4 Pole w/Test Lamps
- Custom Fit Vehicle Wiring
- Wiring Adapters
- Universal Fit
- 4 Flat to 4 Flat
- 4 Flat to 7 Blade
- Plug and Lead
- CURT
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