Tail Light Issue

[GoHorns]

My 2017 Ram 1500 has a towing package, but did not come with a brake controller. So, when we recently purchased a new travel trailer: The dealer installed a Quest brake controller. It was just a matter of two screws, and plug in the wiring harness...

The travel trailer lights (via the 7 way plug) work fine. However, I have discovered that when I plug in my boat trailer (5 way plug) the right rear tail light does not work.... I tested my theory by plugging the boat into my son's truck, and all the lights work fine.

Does this make sense? Should I get an adapter and only use the 7 way plug? Should I unplug the brake controller when pulling the boat? (boat doesn't have electric brakes anyways)

TIA

[Bobbo]

Or, get this 4 pin/7 pin tester and only have to get and store one tester.

[GoHorns]

My mistake... I have the 4 way plug on the boat... However, the problem remains... The lights worked fine on both trucks, now the right tail light doesn't work when the Ram is hooked up... and the only thing that changed is the brake controller install.

I will be purchasing the test lights as suggested by RoyB and see that that tells me.


Thanks!

[RoyB]

My 2010 F150 Ford truck with tow package came with this dual 4-way and 7-way connector assy...

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With the built-in Brake Controller the 4-way and the 7-way connections work just fine here on my setup...

I also carry the two test adapters that tells me all is OK on the truck side which really helps when trouble shooting problems


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Roy Ken

[Bumpyroad]

buy a couple of fittings and "miswire" between them so that the lights work right on the boat trailer. but no brakes on the boat trailer, why not a standard flat 4 instead of a 5???
bumpy

[Bionic_Man]

Your problem shouldn't have anything to do with the brake controller. The power to the electric trailer brakes comes off a different "pole" on the truck plug than the right brake light does.

As far as I know, the RAM wiring comes with a 7-way RV plug, and a 4-way flat plug. If you have a 5 pole plug for your boat (which I have as well), that 5th pole is for the reverse lights, and it turns on a solenoid so that you can back up without your surge brakes locking up.

So, are you using an adaptor to plug your boat in? If not, how are you doing it?

I'd also suggest checking to see if your right turn signal works. If it does, you might have a grounding issue.