Hooking up the brake controller

[LeroyR]

Okay, I looked but didn't find definitive information on this. If I missed it, I apologize.

I just connected my electric brake controller on my 06 Silverado D/A and was wondering about the B+ shunt. Supposedly you don't need to replace it with the 40A fuse which comes with the pigtail if you have the TP2 option. It isn't stated anywhere that I have the TP2 option, but I do have a second battery under the hood, on the passenger side of the truck. This is the basis of my question. Should I leave in the red B+ shunt or use the 40A fuse? Does it matter? What happens if the 40A is installed but the red B+ should be instead?

I've seen conflicting info and need to find out since I will be pulling our 30ft Sandpiper home from our camp.

Any info will be greatly appreciated. Again, apologies if this has been covered and I didn't find it in this forum.

LeroyR

BTW - great web forum here!

[Roy W]

Leroy......On my 2005 I had to remove the red plastic shunt and insert the 40 amp square fuse to activate the B+ or trailer battery charging circuit. I agree, the owners manual and brake pigtail directions are pretty vaque. In any case, as you are facing the fuse box under the hood on the drivers side fenderwell, the square fuse in the upper left corner is the trailer battery charging circuit, and the one in the upper right hand corner is the brake controller circuit. Because these are unique fuses, I bought extras, left them in the original packages, and put them under the lid of the fuse box just so I would have an extra if needed.

[LeroyR]

Thanks for the reply Roy W. I planned on getting extra fuses. Better to be prepared ... just in case.

It's just kind of puzzling (to me) why, with two batteries (in the truck), there would be a "shunt" but a 40A fuse is required when adding (essentially) a 3rd battery (in the TT) - unless the charging system could exceed 40A - which could overload the system. I am assuming the red plug is a shunt because ... well, what else could it be? :confused: :dense:

[Roy W]

Leroy......I think the red plug is more of a "fake fuse" to show you where the real one goes. It's basically just a plastic plug.....Roy

[LeroyR]

Hence the :dense: at the end of my reply. Thanks again! :D

[LouM]

Leroy,

I thought the same as you about the second battery. But I found out the hard way after the third day on the road without plugging into AC power my trailer battery went dead. Almost no lights, no fridge...thought the battery had gone bad. When I hooked up to AC again the battery charged right up. With a little googling I figured out I "did" need the 40amp fuse after all.

Lou

[mdadgar]

Originally posted by LeroyR:
I just connected my electric brake controller on my 06 Silverado D/A and was wondering about the B+ shunt. Supposedly you don't need to replace it with the 40A fuse which comes with the pigtail if you have the TP2 option. It isn't stated anywhere that I have the TP2 option, but I do have a second battery under the hood, on the passenger side of the truck. This is the basis of my question. Should I leave in the red B+ shunt or use the 40A fuse? Does it matter? What happens if the 40A is installed but the red B+ should be instead?
TP2 is probably the dual-alternator option. All Duramaxes have two batteries, so assuming you don't have dual alternators, you need to install the fuse to get power to your trailer.

- Mark

[DmaxMaverick]

TP2 is the RPO for "Auxilary Battery". It is an option, but is automatically added on with the Diesel engine option.

K65 is the RPO for dual alternators.

If you don't install the fuse and leave the shunt in place, and have 12V trailer power, something is wrong. You'll probably overload another circuit trying to draw that much amperage for battery charge and accessories. If your wiring is correct, you must install the fuse to have trailer power. If you have a gasser, it is different, depending on options.

[LeroyR]

Yeah, the 40A was the way to go. Thanks to everyone for their input. I actually called the salesman and questioned him again about needing the red blank or the 40A fuse. Interestingly ... he never called back. Hmmmmm......guess he failed that test. That's okay though ... I like service better. They've never let me down ... through seven GM vehicles.

I had pretty much figured that not connecting the B+ would only affect the charging of the battery on the TT and not the running/tail/stop lamps. Since I was pulling the TT home, it wasn't too much of a concern (ultimately). Still, I wanted to get it taken care of at that time. Not doing so would have probably resulted in problems next season. Coupled with the fact that I would have forgot all about it ... well, not good. ;)

[letsgo]

Hope this isnt hijacking.
It was mentioned that the trailer battery (1 or 2 ??) went dead after 2 days of travel, I have traveled on the road 5 days dry camping without batteries going dead and I refuse to hook up the trucks charging circuit to the trailer, I'll keep 2 separate systems going, the last thing I need is for the trailer to kill my truck on the road.

good luck

drive safe