How do I Tell if the Brake Controller is Bad

Question

Question:

Should I get a continuous 12 volts from the blue wire lead in the back of the truck or should it only read 12 volts when I press either the brake pedal or the brake switch/slider on the brake controller. If I am getting 12 volts all the time is this a sign that the controller is no good.

asked by: James R

0

Expert Reply:

You are correct, you should only be getting output when the brake is applied, or the override switch is activated. It sounds like the controller might be bad, but to make sure, you should probably bench test it before tossing it. Use a circuit tester, and check the red wire that exits the rear of the controller. This wire should only go hot when the brake pedal is pressed. If this checks out ok, then the controller is bad and must be replaced. We have a video that shows how to bench test a brake controller, I'll give you a link to the video below.

If you find that you need to replace the controller, I'd recommend the Tekonsha Prodigy P2, part # 90885. The P2 is a proportional controller for safer, more predictable braking. The P2 is very highly rated because of how easy it is to use.

expert reply by: Mike L

0

Jordan W.

6/15/2020

I took my Silverado 1500 ltz to the dealership because of the recall on the brakes. After I got it back. The trailer brake system keeps popping on. Even tho I never use the trailer brakes. They want to charge me 90 dollars to bring it in. Even tho the recalls where for the brake systems. Never had an issue until I got it back.

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Chris R.

6/18/2020

My best advice here is to take the truck back up to the dealer. I can't imagine why they would charge you just to bring it in when a new issue occurred after they worked on the Silverado. I would try to argue this - they need to at least take a look to see if what they messed with is causing the trailer brake message to pop up.

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Jordan W.

6/20/2020

Funny thing is I got the recalls back in September of last year. Truck ran fine no issues with the brakes or everything. Around in May I decided to take it in and after I got it out I have all these issues now.Well now I have a stabilizer that's popping up. They told me that the trailer brake has nothing to do with the brakes itself thats why they wonna charge me. But I'm paying. I had no issues until I got it back from them.

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Chris R.

6/23/2020

They're right that the trailer brakes run on a completely different circuit than the Silverado's brakes, but that doesn't mean it's impossible to knock a wire loose or do something else that may affect that function when working on the truck.

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Duane L.

4/11/2024

I have a 2021 Colorado with 3.6 cy, towing package. I do not have any voltage on F24 in the under hood fuse block that is supposed to be the positive for a brake controller. Even with the fuse out. Does the 2021 have to be programmed to power the fuse block?

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Mike L.

4/18/2024

@DuaneL I believe that the F24 fuse is for the 12V feed to the trailer connector. Have you checked the fuse in location F27?

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Jose P.

7/8/2024

Hi Mike. I have a 2017 ram 2500 that factory brake controller might stop working my question is if a replace the module and toggle switch. Do I need to get the computer reprogrammed for the new controller. Thanks

Reply

Mike L.

7/10/2024

@JoseP You'd want to check with Ram about that. Typically when you install an OEM brake controller on a vehicle that didn't already have one you'll need to reflash the computer, but I'm not certain if that's the case when you replace and existing OEM controller.

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Cody S.

10/10/2024

Mike, I have a REESE Towpower 8507111 Brakeman IV Digital Brake Control, it is hooked up to the factory wire harness in my 2011 Silverado 1500, I’m having an issue where I have 12v power on the red trailer signal wire. What could be the cause? With power on that wire it keeps the trailer brakes engaged at all times.

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Richard P.

8/16/2025

I am having an issue when i apply the brakes on my truck it seems to be popping a 15a fuse which in-turn controls the running lights on the truck. This is an 03 F250 with the factory wiring harness for the trailer with a tekonsha voyager brake controller. I am hoping this is just the controller gone bad. i have looked at all the wiring and does not appear to be cut, chewed, sliced, etc...

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Mike L.

8/26/2025

@RichardP Have you tried unplugging the brake controller? Does it still happen once the controller is unplugged? What you have happening sounds more like a short in the taillight wiring or the trailer connector. Are the pins in the trailer connector on the vehicle and trailer covered with white or green corrosion? If so, the corrosion could have spread to the interior of the trailer connector causing a short.

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Answer 1

All the brake controller needs to sense a trailer connection so that you can test it is a slight amperage draw on the output circuit. For that you can use a circuit tester like the part #PTW2993 with one pin grounded and the other on the output pin.…

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Answer 2

The blue wire coming from the brake controller to the trailer brakes is the brake power output wire used to tell the trailer to apply the brakes once given the response from the brake controller. Therefore, you should not have a constant charge to…

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Answer 3

I am not entirely sure what process you took so I'll give you some other things to try, or maybe a different way to test the Prodigy P3 #90195. First, sever the blue wire a couple inches from the back of your controller. Then use a circuit tester…

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Answer 4

Assuming that when you tested the resistance of the brakes you were testing the two wires on each magnet and getting 2.0 and 2.8 ohms the magnets on your trailer are not working correctly and will need to be replaced. For 7" brakes you should…

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Answer 5

It is normal to have continuity between the brake(blue) wire and ground(white) wire. The electric trailer brake is an electromagnet when it has power it attracts to the steel inside the hub/drum. If you are having issues with your trailer brakes…

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Answer 6

When initially setting the power on your Prodigy P3 Brake Controller #90195 you will follow the process you stated. I've attached these instructions to further assist. You will get up to 25 mph and release the gas pedal and then fully engage the…

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Answer 7

Absolutely, to install trailer wiring on your 2024 GMC Canyon you will need the Hopkins Multi-Tow 7-Way Blade and 4-Way Flat Trailer Connector #HM11141144. This uses a factory style connector so you will be able to place the connector easily in place…

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Answer 8

It is possible that your trailer brake controller was damaged when the output wire was shorted to ground. There is also a chance the wiring from the brake controller to the 7-way was damaged in the factory harness. You can verify if your controller…

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Answer 9

It sounds like you may have a short in the wiring on your 2022 Ford F-350. You can use a Multimeter #PT29ZR to check this at your 7-way by checking for continuity with the brake wire and any other wire on the 7-way. You can see the terminals in the…

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Answer 10

Since you have the Hopkins Insight Brake Controller, I confirmed with Hopkins that the red light staying on is completely normal. I also confirmed with Hopkins that the red light will not drain your 2010 Ford F-250's battery to the point where…

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Answer 11

If you check out the attached instructions for the Curt TriFlex Trailer Brake Controller #C24VV you can see that the OL code you are getting means that there is an "Overloaded output circuit, trailer brake system fault". Whichever…

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Answer 12

The ER code on a Reese brake controller typically indicates an internal problem that can't be fixed and requires replacing the controller. Since yours is still working normal I'd say that you are probably on borrowed time with it and will…

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How do I Tell if the Brake Controller is Bad

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