12 Volt Accessory Circuit Relay Location in 2019 Ford F-250
Updated 07/22/2019 | Published 07/18/2019
Question:
I have a 2019 F250 which is factory equipped for towing. Yesterday I changed one of my trailer batteries, I mistakenly cross-wired new battery when I was hooking it up, unfortunately, it was still plugged into my running truck, I think I heard like 3 beeps from my cab and then realized what i had done. Fast forward I went to make sure it was charging, it wasnt. Looked in the manual it was a 30amp relay in slot 27 that controlled the tow battery charging relay. I assumed I blew this relay so I went and got two more, installed 1 and still got nothing at the plug. This circuit DID WORK BEFORE, the rest of the trailers lights also still work. I am hoping you could tell me what I am missing
asked by: Eric A
Expert Reply:
Try also checking the relay in slot 37. On your 2019 Ford F-250 the 27 and 37 slots of the fuse box/relay box controls the 12 volt trailer wiring circuit of the 7-way. Otherwise you may have damaged wiring with the short you created.
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