mandrake

Hi, all.

I have a '07 3500 Megacab 5.9 with a little under 81k on the odo.

Yesterday morning, I noticed that the brake lights were on. At first I thought I had left the lights on. I opened the cab, noticed that the light switch was in the off position; but toggled the switch nevertheless. That didn't turn off the brake lights, of course. But I did notice that the trailer brake control light was on.

I tried pumping the brake pedal a few times: nothing.

When I started the truck, the lights stayed on. I pumped the brake pedal a few more times. When I backed up, I heard/felt a slight clunking noise, but the lights went out and everything felt fine. Very weird.

Last night, before bed, I noticed that the brake lights came back on. I opened the cab and the trailer brake control light was on. Now here's where it gets interesting: before I pulled the hood latch, I pulled the emergency brake release; the brake lights and trailer brake control light went out. I disconnected the batteries.

I haven't done anything else to the truck since, but have scoured the forums here. At this point, I'm leaning towards there's a problem with the trailer brake control. But I'd very much appreciate anyone else's input into this bizarre situation with my poor truck.

RyeThomas

Do a search for the brake light switch, common issue on third gens. You can get a replacement for around $20 from Napa or I believe the OEM replacement is around $40-50. Replace it, takes no time its plug and play.

CrazyCooter

I have have had the problem on and off over the past few years with it happening more often a few months ago....

I also had a few customers with 3rd gens complaining of the brakes dragging while towing trailers with electric brakes right after I fixed mine. One had already had a new pedal switch installed but the problem had come back.

Bend the tang on the pedal that contacts the brake switch a little with a prybar and your issue will likely be fixed!

mandrake

Thank you for the replies!

Colo_River_Ram

Blow out the switch and related contacts while your in there, my switch plunger got stuck on mine a shot of air fixed it.

mustang2mach1

I had the same issue and like Crazy said a shoot of air in the pedal switch and a little bend in the metal tab that holds it and all is fine.

Double check that the brake pedal come all the way back up when released.

mandrake

Thanks again for all the great advice!