Troubleshooting Overload Code on Curt TriFlex Brake Controller After Replacing 7-way

Updated 02/23/2026 | Published 02/17/2026

Products Featured in This Question

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

(981)

$135.95

10 Gauge Wire - Blue Primary - Per Foot

(107)

$1.71

Question:

I have a Curt Triflex brake controller on my 1994 Suburban. It was working fine. However I replaced the vehicle side socket due to a broken weather flap on the old one. I then tested all the lights and brakes and everything checked out. I unhooked the trailer ran errands and noticed that the controller is now displaying an OL code. I’ve removed and cleaned the ground at the socket again which I did move and clean, before checking everything the first time. Any help would be appreciated.

asked by: Mike

Expert Reply:

Hey Mike,

Really sorry to hear about all the headache. The Overload code on your Curt TriFlex # C24VV is triggered by a short on the blue brake output wire. I'd double check that the brake output wire is connected correctly to your 7-way, it should be the bottom right pin assuming your 7-way is installed in a way that the little tab on the trailer side 7-way is pointing up.

If that wire is connected right there, then you'll want to cut the blue wire on the back of the brake controller about 6" back. Doing that should clear the code, and hitting the manual override and brake pedal should not make it say OL again. If this is the case, then the blue wire running from the brake controller to 7-way is damaged and you'll need to replace it with new wire # 10-1-1.

Let me know what you find and we can go from there.

What do you tow with your Suburban?

expert reply by: Samuel C

Mike

2/20/2026

I’ve double checked the wiring at the plug. So I clipped the blue wire at the back of the controller and the controller is still blinking “OL”. Please advise. I pull a 7x14 Haulmark Grizzly cargo trailer, daily for work.

Samuel C.

2/23/2026

@Mike If the brake controller blue wire is disconnected and still giving an OL code, the brake controller has an internal error and will need to be replaced. Did the brake away pin on the trailer get pulled with the 7-way plugged in to the truck still?