My 2002 Ram 3500 is a 2nd generation truck whereas your Ram 1500 is a first year 3rd generation truck, so this suggestion may or may not apply. On my truck, there is a power distribution panel containing fuses, circuit breakers and relays under the hood on the inner fender well on the driver's side of the truck. Under the cover of this power distribution panel is a label that identifies all the fuses, circuit breakers and relays and the circuits they serve. On my truck, the trailer brake circuit and the trailer +12VDC battery charge circuit were not enabled as the truck shipped from the factory. When we ordered the truck and took delivery, there was a plastic bag in the glove box that included a trailer brake harness and circuit protection for the trailer brake and trailer battery charge circuits that I had to plug into the power distribution panel. Check the power distribution panel to ensure that the trailer brake and battery charge circuit devices (see the label under the cover) are present and functioning.
2016 Ram Longhorn 3500 Dually 4x4 CCLB, 385/900 Cummins, Aisin AS69RC, 4.10
2014.5 DRV Mobile Suites 38RSSA #6972
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