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Problem with LED trailer lights

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Old Mar 31, 2017 | 03:46 PM
  #16  
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That's my point. It can't be the controller unless the controller has a power source.

Steve
 
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Old Apr 1, 2017 | 09:47 AM
  #17  
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Originally Posted by DonZ1029
The controller goes dead after the key is shut off.
You sure about that? Brake lights always work even when the key is off, so there can still be some live power in the unit at all times.
 
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Old Apr 1, 2017 | 10:30 AM
  #18  
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Mine powers down. It is lit when the ignition is on, but goes off when the ignition is off. I just checked mine with my meter and I have nothing on any pin on my seven pin with the key out of the ignition switch. Anyone have anything different?

Steve
 
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Old Apr 1, 2017 | 10:33 AM
  #19  
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Originally Posted by alloro
You sure about that? Brake lights always work even when the key is off, so there can still be some live power in the unit at all times.
Yes, you work the brake pedal to feed power to the red controller lead, but power to and through the controller to the blue lead feeds off the black lead to the controller. I think the black is fed by the relay for the trailer brakes.
 
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Old Apr 4, 2017 | 07:29 PM
  #20  
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Here is the response I received from Tekonsha regarding the Prodigy II brake controller:
The Prodigy P2 should have nothing to do with your brake lights. That being said it does sound like the LED lights are catching the trailer detection signal from the control. What you are describing would tell me either the trailer is not wired correctly or you appear to have a short between the Electric brake circuit and the Brake lights on the trailer. If in fact the trailer manufacturer wired Brake Lights to the Electric Brake circuit, this needs to be corrected as it is not DOT compliant. I would unplug the brake control and activate the brakes on the truck, with the trailer plugged in, and see if there are any lights that no longer function.

Looks like I have a little testing to do next time I'm out where my trailer is located.

Don Z.
 
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Old Apr 5, 2017 | 09:04 AM
  #21  
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my P3 will hold the trailer brakes for 10 minutes or something when turned off. I dont use this feature on mine (as usually once I level my TT I chock the wheels and unhitch), but it doesnt mean yours wouldnt have this same feature.

Just a thought.
 
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Old Apr 5, 2017 | 09:44 AM
  #22  
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Originally Posted by The John
my P3 will hold the trailer brakes for 10 minutes or something when turned off. I dont use this feature on mine (as usually once I level my TT I chock the wheels and unhitch), but it doesnt mean yours wouldnt have this same feature.

Just a thought.
If that were the problem, it should mean constant lights. His blink off and on.
 
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Old Apr 8, 2017 | 07:45 PM
  #23  
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Originally Posted by RV_Tech
Yes, you work the brake pedal to feed power to the red controller lead, but power to and through the controller to the blue lead feeds off the black lead to the controller. I think the black is fed by the relay for the trailer brakes.
I had to use my trailer today, so I had a chance to do some testing. When I unplugged the Prodigy from the wiring harness, the blinking stopped. I swear there was a post that discussed seeing if the brake lights worked without the brake controller connected, but I couldn't find the reply.

While the Prodigy was unplugged from the truck, I pressed the brake pedal. I had a working left brake light and nothing on the right side. Prodigy was reconnected and both brake lights worked when the pedal was depressed. Oh yeah, the blinking started as soon as the Prodigy was reconnected to the truck.

I guess I get to spend some time under my trailer figuring out where they crossed the brake wire with the brake light wire.

Don Z.
 
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Old Apr 8, 2017 | 09:02 PM
  #24  
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Originally Posted by DonZ1029
I had to use my trailer today, so I had a chance to do some testing. When I unplugged the Prodigy from the wiring harness, the blinking stopped. I swear there was a post that discussed seeing if the brake lights worked without the brake controller connected, but I couldn't find the reply.

While the Prodigy was unplugged from the truck, I pressed the brake pedal. I had a working left brake light and nothing on the right side. Prodigy was reconnected and both brake lights worked when the pedal was depressed. Oh yeah, the blinking started as soon as the Prodigy was reconnected to the truck.

I guess I get to spend some time under my trailer figuring out where they crossed the brake wire with the brake light wire.

Don Z.
Yes, there is a fundamental problem in your wiring.

Steve
 
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Old Apr 8, 2017 | 09:05 PM
  #25  
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I would suggest starting with the back of the seven pin on your truck before moving to the trailer.
 
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Old Apr 8, 2017 | 09:23 PM
  #26  
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Originally Posted by RV_Tech
I would suggest starting with the back of the seven pin on your truck before moving to the trailer.
I'm pretty sure my truck is good. I have another gooseneck trailer that has no electrical issues when connected to my truck. But I will verify the 7-way pin out on the truck just in case...

Don Z.
 
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Old Apr 8, 2017 | 09:29 PM
  #27  
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Originally Posted by DonZ1029
I'm pretty sure my truck is good. I have another gooseneck trailer that has no electrical issues when connected to my truck. But I will verify the 7-way pin out on the truck just in case...

Don Z.

If that is the case, next stop would be the J box on the trailer.

Steve
 
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Old Apr 9, 2017 | 11:46 AM
  #28  
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Originally Posted by RV_Tech
If that is the case, next stop would be the J box on the trailer.

Steve
Next stop should be to take it back, without the trailer brake controller plugged in and have the dealer figure it out. (once they figure it out - they'll probably use another trailer and/or truck to verify where the oddness is) plug in your brake controller and see what happens.
 
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Old Apr 9, 2017 | 01:06 PM
  #29  
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Originally Posted by Misky6.0
Next stop should be to take it back, without the trailer brake controller plugged in and have the dealer figure it out. (once they figure it out - they'll probably use another trailer and/or truck to verify where the oddness is) plug in your brake controller and see what happens.
I know it's under warranty but the dealer is a 3 hour drive from me. By the time I get there, let their service folks look at it and return home, I'll have at least 8 hours of time invested. I'm pretty sure it won't take 8 hours to check the wiring and get things sorted out.

Don Z.
 
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