Does Flicker of Brake Output Circuit on Trailer Wiring Mean There's an Issue

Updated 08/12/2024 | Published 12/12/2020

Question:

Im using the POLLAK 12741EV tester on a 2013 RAM 2500 with factory brake controller and trailer wiring. Successfully pulled my trailer for 6 years. Recently the dashboard communications began reporting problems with the trailer brake connection. The POLLAK tester Brake indicator shows a flicker when installed. The truck reports No Trailer Connected. Running the manual lever to full on results in the same signal indication. Flicker The truck has been taken to the dealer and tested. No problems were found in the braking circuit. The trailer wiring indicates a low resistance on the brake wire which would seem to indicated the brakes are connected. Is the indicator flickering an indication of a normal output? Should it go full bright with full manual lever operation?

asked by: James W

Expert Reply:

The flicker you are seeing on the brake output circuit of your vehicle is normal. Brake controllers will lightly pulse their output circuit to check to see if a trailer is connected due to the amperage draw of the brake magnets.

So what this all tells me is that your issue is most likely on the trailer side of the equation. This can be as simple as corrosion on the pins of the trailer wiring connector or it could be damaged wire, bad brake magnets or the grounds of the assemblies having issues as well. You'd basically want to go over the entire circuit looking for any obvious signs of a short and fix as needed.

expert reply by: Jameson C

Dan E.

7/12/2024

I have the same question that wasn’t answered. Should the test light go full bright when the pedal is pressed or brake controller lever is activated? Does a dim pulse with no pedal and brighter pulse when engaged mean the tow vehicle is most likely not the issue?

Jameson C.

7/15/2024

@DanE Yes it should go full bright when the manual override lever is slid or brake pedal is pressed and output is turned up. Pulsing indicates the controller is just testing for a trailer connection.

Josh H.

7/19/2024

And should the truck also report that a trailer is connected? On my 2016 RAM, it shows no trailer connected, and when there is no trailer connected, actuating the manual override on the brake controller does nothing. There must be a trailer connected for the override switch to function. I've also emailed Pollak directly for clarification and have not received a response.

Jameson C.

7/19/2024

@JoshH Yes it should show a connection to a trailer and if one isn't connected you aren't going to be able to use the override lever.

Josh H.

7/19/2024

@JamesonC ok then, so that would indicate that either there is an issue with the trailer brake controller (truck side, not trailer side as your original answer suggested), or that the Pollak tester does not properly function with the RAM trailer brake controller. Do you know if the Pollak tester has been tested and verified to work in this manner on 4th gen RAM 2500's with the factory ITBM?

Jameson C.

7/21/2024

@JoshH It could be the brake controller but more than likely the circuit tester is not able to simulate the load of brake magnets and therefore is saying there isn't a trailer connected.