Engine retarder/Trailer brakes

[QA2FalconRet]

I have a 2002 Phaeton DP w/330 Cat 3126 and tow a tandem axle trailer with electric brakes, when I us the retarder I get my trailer brakes also, this is indicated on the brake controller, so I can not us it on long down hills, I assume the retarder is some how connected to the brake lights and that is applying the trailer brakes. I would like to disconnect that but don't have a clue where to start looking for where it connects. Does anyone have any ideas? I want the trailer brakes when I apply the MH brakes. Thanks

[Bigd9]

What I do know is you can change the way the retarder works. It can be reprogramed not to illuminate the brake lights. What I can't remember is who can reprogram it. Cat, or Allison. I think it is an Allison reprogram, but I'm not positive.

Also you can get a trailer brake controller that doesn't use the brake lights but uses a internal sensing circuit to activate the trailer brakes.

[FIRE UP]

Originally Posted by QA2FalconRet

I have a 2002 Phaeton DP w/330 Cat 3126 and tow a tandem axle trailer with electric brakes, when I us the retarder I get my trailer brakes also, this is indicated on the brake controller, so I can not us it on long down hills, I assume the retarder is some how connected to the brake lights and that is applying the trailer brakes. I would like to disconnect that but don't have a clue where to start looking for where it connects. Does anyone have any ideas? I want the trailer brakes when I apply the MH brakes. Thanks

QA,
Disconnect what? The retarder or, the mechanism that activates the trailer brakes when the retarder is in operation? The operation of auxiliary braking, i.e. just about any form of it, and the inclusion of brake lights, has been discussed just a few times on here. I'd say about, 98% of the auxiliary braking, exhaust brakes, Jake Brakes, Retarder(s) etc. all activate the coaches brake lights. You will find, on rare occasions, one that doesn't from the factory.

But, I'm not all that familiar with electric brake controllers so, I'm assuming that part of the controllers functions are tied into the coaches brake lights. And if that's the case, ANYTHING that activates the brake lights, i.e. Retarder, will also effect the brake controls.

And, as you more than likely know, the assistance from any auxiliary brakes, retarders, exhaust brake, Jake Brake etc. is of ultra value when descending long grades or, any grades for that matter. So, disconnecting it could have some pretty detrimental effects. Besides that, if you disconnect it, then you'll have to use your service brakes a heck of a lot more and, that too will cause your trailer brakes to engage.

Now, if you were to install a disconnect switch in the wire that leads to the trailer brakes and, simply turn that switch OFF when the retarder is in use, well, that could work but, you'd have to make sure you have some sort of reminder that it's OFF and, is needed in other braking situations. Good luck.
Scott