Sounds like your feeding current back through the system when you plug the trailer lights in. Do your headlights have a single bulb with high/low beams? If so, the bulb is probably bad on the side that does not work on high beam. When you plug the trailer in, it is most likely sending current to the high light (low beam) and that is what you are seeing not the high beam light.
2007 Dodge RAM 3500 Laramie Quad Cab LB 4WD
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Maintenance & Repair
My daytime running light drivers side not on , when I manually turn headlights on low beams work both sides , but when I hit the high beams only passenger side is on ????
2007 Dodge RAM 3500 Laramie Quad Cab LB 4WD
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Maintenance & Repair
Ran out of fuel. added fuel and truck starts but no power when when in drive. any suggestions
2010 Dodge RAM 3500
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Maintenance & Repair
Have no oil pressure cold or hot after long shut down for 40-60second then have 40psi at idle 70psi at 2000rpm no flucuation after pressure comes 5.9 Cummings
1996 Dodge RAM 3500
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Maintenance & Repair
I have a 2003 dodge ram 3500 with a 5.7 hemi and I recently put a new throttle body on it because it was throwing several codes indicating that it needed replaced after installing it and clearing ...
Dodge RAM 3500
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Maintenance & Repair
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