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Electric brake controller: Relay under hood???

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Old Mar 2, 2007 | 06:01 PM
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Electric brake controller: Relay under hood???

Just plugged in Prodigy brake controller with the Ford harness and nothing on display. I have the 30amp fuse in the fuse panel under the dash but read on these forums there is a relay or fuse under the hood too.

Anybody know where the relay or fuse should be under the hood? I'm guessing this is why the brake controller isnt working???

This is for a 2003 F250 6.0 Liter
 
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Old Mar 2, 2007 | 06:31 PM
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I do not think there is a relay for the brake controller...if so...I have no clue what it would be used for....hopefully someone can chime in and let you know. I have a Prodigy and it works fine with the Ford harness...
 
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Old Mar 2, 2007 | 06:37 PM
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Does your display have something on it all the time? Maybe I should hookup my trailer. After reading the manual, I assumed that once you plugged it in the display would come on.
My old controller (different truck) only lit up when trailer was plugged in.
 
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Old Mar 3, 2007 | 12:15 AM
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On my 99 there was 2 relays and 2 maxi fuses that had to be put in the box under the hood to get my trailer brakes and everything to work. These are usually found in the same bag as the trailer brake harness. You should be able to find there locations in the owners manual.
 
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Old Mar 3, 2007 | 07:04 AM
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From: Drain Oregon and Sacramen
Originally Posted by nmlaz
Just plugged in Prodigy brake controller with the Ford harness and nothing on display. I have the 30amp fuse in the fuse panel under the dash but read on these forums there is a relay or fuse under the hood too.

Anybody know where the relay or fuse should be under the hood? I'm guessing this is why the brake controller isnt working???

This is for a 2003 F250 6.0 Liter
I just plugged the prodigy into the Ford plug under the dash and it has worked fine ever since. Did your truck come from the factory with the towing package? If it didn't it may be missing the relays under the hood.;
 
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Old Mar 3, 2007 | 07:30 AM
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If you have towing package you dont need the breaker. i just recently installed a draw tite controler on my 98 f250... on the plug in under the dash the instructions said that the brake light wire goes directly to ground after the brake pedal on the truck is released .......thus inturn when you manually applied the brakes on your controler it will fire it......it said you have to run your brake light wire from your controler directly to the cold brake wire on your brake light switch on your truck ..........ford wiring mistake hope this might help you.
 
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Old Mar 3, 2007 | 08:42 AM
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My 01 truck came with the plug and all the relays and fuses in the glove box. You need the relays and fuses under the hood . Look in your owners manual it will tell you which ones and where they go.
 
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Old Mar 3, 2007 | 09:52 AM
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I have an 03 with the 5.4L. I installed my brake controller with the Ford harness, and I had to actually have my trailer plugged in before anything lit up. But it worked (works) just great. Mine is a Tekonsha, but yes, try hooking up your trailer. Or you can get one of those testers that was talked about on another thread (or maybe even another forum...can't remember for sure).
 
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Old Mar 3, 2007 | 10:43 AM
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the under hood fuses and relays are only on 2001 and older SD's
 
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Old Mar 3, 2007 | 10:43 AM
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From: SW ND
Location 6 20A TT* Stop/Turn

Location 38 20A TT* Parklamps

Location 39 15A TT* Backup Lamps

Location 101 30A TT* Electric Brake

Location 115 20A TT* Battery Charge

Location 211 Backup Lamps Relay (Diesel Engine Only)

Location 305 TT* Battery Charge Relay


*TT= Trailer Tow

All from the 2003 F250/350/450/550 Owner Guide Pages 177-181

All that is needed is a 30A Fuse and a brake controller to make the electric brake Circuit work. The other relays are for TT Battery Charge, and TT Reverse Lamps. The exact same as my 2003 F150.
 
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Old Mar 3, 2007 | 03:01 PM
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My Prodigy shows either one or two red dots, depending on whether the Boost is on or not. They will go off after a few minutes when parked. Touching the brake pedal brings them back on. It is the same whether the trailer is plugged in or not as I remember.
 

Last edited by dmcconaughy; Mar 3, 2007 at 03:03 PM. Reason: correction
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Old Mar 4, 2007 | 08:18 PM
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Smile Mistery Solved!

If anyone has the same problem... here goes. The 30A relay in slot 101 was burned out. I thought I checked this but after doing multi-meter test on pigtail no power was going to the brake controller.
There are no under hood relays or fuses for the 2003 SD.
The prodigy lights up even when not plugged into trailer.'

I appreciate all your help and replys. Next time I'll be more thorough.
 
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Old Mar 5, 2007 | 09:18 AM
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From: Drain Oregon and Sacramen
Originally Posted by nmlaz
If anyone has the same problem... here goes. The 30A relay in slot 101 was burned out. I thought I checked this but after doing multi-meter test on pigtail no power was going to the brake controller.
There are no under hood relays or fuses for the 2003 SD.
The prodigy lights up even when not plugged into trailer.'

I appreciate all your help and replys. Next time I'll be more thorough.
Yreka!! great, was looking forward to hearing the fix and glad it was something simple.
 
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