Troubleshooting 12 Volt Accessory Circuit of 2016 Ford F-350 Not Being Active

Published 11/20/2019

Products Featured in This Question

Hook Probe Circuit Tester

(66)

$14.40

10 Gauge Wire - Blue Primary - Per Foot

(108)

$1.61

40 Amp In-Line Circuit Breaker - Perpendicular Mount Bracket

(98)

$9.89

Question:

My trailer battery charge plug does not work , Turn lights work and running and break lights work Also break adjust no on in dash f 350 diesel 2016

asked by: Phil B

Expert Reply:

It's most likely a blown fuse under the hood of your 2016 Ford F-350 that's not allowing the charge circuit of your 7-way to be active. That would be what you should check first. Next make sure there's no corrosion on the 12 volt pin of the 7-way. This would be the pin in the 1:00 position. It's very common that corrosion prevents trailer wiring circuits from working properly. If the connector ends up being damaged you can replace it with the part # HM40975 for a 7 and 4-way connector.

Another option you have would be to bypass the factory wiring and run a 10 gauge wire like part # 10-1-1 (sold by foot) from the 12 volt pin to the positive battery post through a breaker # 9510 and you'll have the circuit active.

expert reply by: Jameson C