Troubleshooting Curt Triflex Brake Controller 51140 That Does Not Activate Trailer Brakes

Published 08/15/2018

Products Featured in This Question

Curt TriFlex NEXT Trailer Brake Controller - 1 to 4 Axles - Proportional

(993)

$141.95

Hook Probe Circuit Tester

(65)

$12.94

Brake Adjustment Spoon for Drum Brakes

(222)

$9.58

Question:

Trailer brake worked perfectly last year. This year, on route to destination brakes did not respond at all on board trailer. Tried re calibration, stopped position with foot off the brake set power adjustment to 2.0 and sensitivity to L1. Ended all the way up to 9.0 and L3, Brakes for trailer still did not engage. Unplugged trailer from truck, used electrical cleaner and sprayed both connections. Trailer is fairly new 2015 jayco jayflight 26bh trailer has less than 3000kms to date travel distance between us and previous owner. Truck 2008 dodge ram 1500 5,7L Hemi There are no codes on the Curt display to indicate a problem. Any assistance you could provide would be greatly appreciated.

asked by: Drew F

Expert Reply:

I suggest performing separate troubleshooting on the trailer's brakes to see if they will operate correctly with direct 12V power input. Eliminating the controller and truck wiring variables often makes troubleshooting easier.

You can use your Ram's battery (or a fully-charged extra 12V battery you might have handy) to test the trailer brakes when the trailer is not connected to the vehicle. If you refer to the linked photo of a trailer-side 7-way plug you will see the two plug contacts that should be connected to your test battery's ground and hot terminals. A set of jumper cables and two lengths of wire can make this process of applying battery power pretty easy.

With direct connection of the charged battery to the trailer brake circuit you should be able to hear a gentle humming from the magnets in the brakes. This tells you that the trailer's brake circuit is working. If you can hear this humming but the brakes do not stop the wheel from rotating when you try to spin it you may just need to adjust your brake tension using the star wheel adjuster near the bottom of the assembly. Since your controller is NOT throwing error codes this suggest the overall circuit is intact when the trailer is connected but that the brakes themselves are not applying enough pressure to your drums.

We offer a brake adjustment spoon tool # W80630 but a flat blade screwdriver works well too. Please refer to the video I linked for you that shows how the tool or screwdriver is used to adjust brake show pressure.

If the direct power input engages the brakes properly then this will suggest that the controller or vehicle wiring are the issue. You can easily test the controller by applying a circuit tester like # PTW2993 to the blue output wire at the back of the controller. Ground the tester and apply it to the blue output wire while you press the manual override control. Set the TriFlex to maximum power and maximum sensitivity for this test. You should detect the braking signal on the blue wire when the press the override. If so, move to the vehicle 7-way and repeat. Please refer to the other linked photo to see the socket contacts to test. If the brake controller signal is present at the back of the controller but not at the 7-way, then you know the issue is in the wiring between the controller and the 7-way vehicle socket.

In this case try tracing that brake circuit wire looking for signs of cracked or worn insulation that could be shorting the controller output.