Brake Controller

[wxmn6]

When I was installing Jordan Ultima brake controller on my truck today, I saw the 40amps fuse that came with the GM trailer harness. I checked the owner manual and saw that there are two locations for the fuse for "Accessories/Trailer" which is "Stud 1" and "Stud 2" if I remember correctly. The fuse block is located in the engine room on driver side. According to the sticker on the back of fuse block cover, it said that "Stud 1" is 40amps and that "Stud 2" is 30amps. I see that 30amps fuse is already in the "Stud 2" slot and the brake controller is working (without trailer connected). At first, I thought that the "Stud 1" is for power supply to the brake lead (blue) to the rear of truck. But when I went to test the brake wire for trailer at the rear of truck in the harness plug with truck brake applied, the test light lits dim. So I inserted the 40amps fuse in to see if the light lit brighter but I still get the same result. Now I am wondering what the 40amps that came with GM trailer harness is for? Can anyone explain?

I have not connected the trailer to my truck yet, but when the fuse issue get cleared up, then I will be able to test and adjust the brake controller. But I have a question. I am a lawn care professional and I have a 6'7" by 12' single axle trailer to pull. Should I make the adjustment (locking up the trailer brake) when the trailer is empty or loaded? Thanks.

[ 10-06-2002: Message edited by: wxmn6 ]</p>

[wxmn6]

Oh wait, I just thought of something. Could the 40amps fuse be for the power (battery) feed to the breakaway system battery on the trailer?

[FirstDiesel]

IIRC it's the auxilary power connection for the trailer.

[Flyboy]

The 40 amp is for the trailer battery charging. For campers and such. Adjust the controller with the load you usually haul on the trailer. Once set, remember or write down the amp reading on the controller. Then do the same thing with the trailer empty, then all you have to do is adjust the amp reading when you change loads.

[letsgo]

wxmn6 nope You need a battery in the trailer for the breakaway to work.
Also when I installed the jordan I didnt have to install any fuses and the brakes work AOK.
When you hook up the trailer electrically apply brake and remember the max. amperage this is your referance, cause if it changes you have a problem, jordans instruction set is pretty good.

good luck

[wxmn6]

My trailer does come with battery for breakaway system. I guess this is the fuse for the wire to charge the trailer breakaway battery.

[oneton]

I had to use the 40 amp fuse on my 02 with the factory trailer harness. I had no power what so ever at the plug until I installed the fuse. Never had a problem afterward.

[GBurton]

wxmn6

You are correct, the 30 amp fuse is only for the brake controller. If you have a battery in the trailer for the break-a-way system there is only one way to keep that battery charged. You need to install the 40 amp fuse so you have 12 vdc power to the trailer to keep the battery charged.

George