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Wayne, Journeyman
Category: Medium and Heavy Trucks
Satisfied Customers: 9465
Experience:  worked on, Gmc, Macks, Freight liner,Mercedes Benz,,Ford, sterling
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I've got a problem with a trailer brake controller in a 2000

Customer Question

I've got a problem with a trailer brake controller in a 2000 Hino FA. The unit works manually, but not with the pedal. There are 2 wires on the switch connected to the pedal- one is hot when the pedal is up, but the other does not get hot when the pedal is depressed, but both the truck and trailer brake lights function with the pedal down. I don't have a wiring diagram for the truck and don't know if there is something I'm missing.
Submitted: 2 years ago.
Category: Medium and Heavy Trucks
Expert:  Wayne replied 2 years ago.
Hi I'm Wayne
I will help you with this
Thank you for requesting me
there is a problem with the signal wire
here is a troubling shooting guide
Customer: replied 2 years ago.
I've already utilized e-trailers website and called tekonsha directly, but neither could provide assistance. The only thing I've been able to learn is that I am not the only one who has had this problem as I found this quote on heavy equipment forums:"Has anyone here ever installed a brake controller on a Hino? These trucks ground a relay at the brake pedal switch (instead of switching the 12V hot side of the brake light circuit, as in most vehicles), so the red brake controller wire - if installed at the switch - destroys the controller (ask me how I know) because the controller feeds 12V to that circuit and when it goes straight to ground via the switch circuit it burns a trace on the controller board. Controllers are meant to see a switched +12V at the brake switch, but Hinos are NOT wired that way.I wired to the switched hot side of the brake relay instead; that doesn't burn up the controller, but now the brake lights are on constantly (pedal applied or not) anytime the controller is plugged in (the controller may be faulty, but I don't want to jump straight to that conclusion). Does anyone here have any experience wiring a brake controller into a system incorporating a relay?Thanks ahead of time for any help! I'm at my wits' end here."
Expert:  Wayne replied 2 years ago.
Well that is interesting
how did you wire it up, hot or ground
Customer: replied 2 years ago.
I bought the truck with the controller already installed and am now trying to figure out the right way to hook it up, because it doesn't work as is. It is currently wired in the conventional manner and doesn't work except manually.
Customer: replied 2 years ago.
This is the response to the long quote above, but it doesn't make sense to me.
"The control side of the factory relay uses the negative side of the circuit for switching purposes which is unorthodox but fine, it will work. I am guessing they save some copper as its closer to ground most times than the positive side of the circuit at hand. Chances are that the relay is making and breaking the positive side of the circuit. You can make your connection on the load side ( you guys refer to this as the 'cold' side) of that relay and it will work the same as the traditional system that you are used to. Your brake lights are not coming on because you tied into the wrong side of the relay.The controller back feeds 12+ to the brake switch wire, that's how the lights work when manually controlling the brakes. The controller burned up because you tied it directly to ground and created a condition for maximum ampacity. The lamps are resistance in the circuit which brings the current down. Good luck and I hope this makes sense and helps you out."
Expert:  Wayne replied 2 years ago.
Doing research here my self,
I contacted Toms trucks, Hino Parts
They told me the controller MUST be a Hino part
what brand is your and a P/N if you have
Customer: replied 2 years ago.
The controller is a Tekonsha Voyager and I don't know what the P/N is
Expert:  Wayne replied 2 years ago.
Thank you for that
Ok that is not for Hino, Truck
it is for cars
wrong controller , that is your problem
Customer: replied 2 years ago.
I'm sorry Wayne, but that is a load of BS. I'd like to know where you came up with that. I've already talked to several Hino dealers and not one of them said anything about the brand of controller being an issue. If they sold Hino branded controllers, I'm sure they would have tried to sell me one.
Expert:  Wayne replied 2 years ago.
I received that from Chat at Tom,s Hino Truck Parts
On Chat,
Here is the line send them a message yourself see what they tell you
Customer: replied 2 years ago.
I called Tom's and they didn't answer the phone; they wanted me to leave a number. I called another Hino dealer parts department and was told that any brand brake controller would work just fine so long as it was installed correctly, and that seems to be the the question that you can't answer.
Expert:  Wayne replied 2 years ago.
HI ***** am going to opt-out of this,
put it back to the board for another expert to answer
Don't reply,or rate me as it locks the question back to me
and Blocks other Experts
Sorry I could not help

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