Installing 7-Way and Wiring for Auxiliary Battery Charging
Updated 07/03/2018 | Published 07/02/2018
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Question:
Hi, Ford E150 hi top conversion van 2003 I want to charge an auxiliary battery while the van is running. I see relays and fuses for charging a trailer battery while running, but the van only has a four pin connector or I would just tap in there. Where/how do I convert to seven pin and how do I find the lead for the pin that is used for e auxiliary battery? Thank you
asked by: Karl
Expert Reply:
For your 2003 Ford E150 hi top conversion van, because you have a 4 way connector, you can use the Adapter 4-Pole to 7-Pole and 4-Pole # 37185. This will connect to your 4-way and then you can simply connect the white ground wire to a bare metal surface and then use # 10-1-1 sold by the foot to connect the black wire on the connector to circuit breaker # 9510 and then to the positive terminal on your vehicle battery. This will get your vehicle ready to send the 12V power.
Then on your trailer side, the pin corresponding to the vehicle side 7-way in the 1 o'clock position will be your 12V power. That wire will also normally be black like # H20046 and will connect directly to the positive terminal on your auxiliary battery. The negative terminal of that auxiliary battery will simply connect to the trailer frame for ground.
This wiring configuration will provide a maintenance charge for that auxiliary battery. For a full charge of a depleted battery you will still need to use a battery charger like # 329-GENIUS5 or a DC to DC charger like # 331-BCDC1225D.
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