Verifying OEM trailer brake controller output voltage

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aanorm69

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I am trying to verify that my 2014 Longhorns trailer brake controller is in fact putting out the requisite 2-12 vdc. When I connect a volt meter between to neutral and brake output pin it fluctuates between 1.0 and 1.2 volts. It doesn't matter if I apply the brakes or if I manually move the paddle to the left. What is the best way to verify I am getting a changing voltage at the truck connector? Thanks
 

AFMoulton

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I am trying to verify that my 2014 Longhorns trailer brake controller is in fact putting out the requisite 2-12 vdc. When I connect a volt meter between to neutral and brake output pin it fluctuates between 1.0 and 1.2 volts. It doesn't matter if I apply the brakes or if I manually move the paddle to the left. What is the best way to verify I am getting a changing voltage at the truck connector? Thanks

You need a special tester. There is a thread about this issue on here, and there was a TSB, and a reprogram fix that has seemed to work. Let me see if I can find the thread


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rcmedic

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Does anybody know if it is standard practice for FCA/Dealership to charge $76 to reprogram the trailer brake controller to make it work properly?
 

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BossHogg

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I am trying to verify that my 2014 Longhorns trailer brake controller is in fact putting out the requisite 2-12 vdc. When I connect a volt meter between to neutral and brake output pin it fluctuates between 1.0 and 1.2 volts. It doesn't matter if I apply the brakes or if I manually move the paddle to the left. What is the best way to verify I am getting a changing voltage at the truck connector? Thanks

Best way to test the ITBM is to connect a trailer and see if the trailer's brakes engage.

The brake controller doesn't output DC power, it provides a modulated power stream consisting of on/off pulses. The more on-time pulses equates to more output power. Google "PWM" for an in-depth understanding. The brake controller will not provide any output unless a trailer is connected. The controller senses the brake line or an inductive load to determine if trailer brakes are connected.
 

AFMoulton

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Does anybody know if it is standard practice for FCA/Dealership to charge $76 to reprogram the trailer brake controller to make it work properly?

Cost me 155 at my dealer to do it. So I’d say 76 is a good deal.


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Cardhu

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If its working, it might not be displaying on your meter because the meter isn't fast enough to see the pulses. If you have a fancy one, put it on VDC PP (peak to peak) and hold on max.
 
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