2012 Ram with OE Brake Controller Not Reading Trailer

Updated 11/20/2012 | Published 11/17/2012

Question:

hi having trouble w/my new dodge i tow a small trailer 7 prong plug w/brakes went over a small speed bump and lost my brakes the dash display dosent see the trailer , small symbol of a trailer with a line thru it ???. and i have NO trailer brakes should i see a voltage on that wire when brakes are applied and if so what and i seem to not be getting any on that wire ??. is dodge having problems with these ??

asked by: CRAIG

Expert Reply:

I have not heard of any issues with the Ram OEM brake controller. Just to be sure, I spent a few minutes looking through the Ram forums on the internet, and did not find any references to problems. Because the controller is proportional, you will not see much output on the wire unless the vehicle is in motion. However, you should show voltage when the manual brake switch on the controller is actuated.

The easiest way to begin troubleshooting is to try the trailer with different vehicle or the vehicle with a different trailer. If the trailer works fine with another vehicle, you have confirmed that the problem is with your Ram. If the Ram works fine with another trailer, you have narrowed the problem down to your trailer.

If the problem exists on the vehicle, you would want to have your Ram dealer look at it (I assume it is still under warranty). If the problem exists on the trailer, you would want to trace the brake output circuit (typically a blue wire) back from the trailer connector to the brake assemblies. Look for any pinched wires or loose connections. Make sure the wire insulation is not worn or cracked. Check the connections at each brake assembly. The brake magnet in each brake assembly will have two wires exiting it. One wire from each magnet should ground to the trailer frame, and the other should connect to the brake output circuit. You can pull the brake drums off and check the brake assembly magnets for excessive wear. If you can see the copper wire on the interior of the magnets, then the magnets are worn to the point where they need to be replaced.

expert reply by: Mike L