GM trailer brake - service system on DIC?

[Braddock54]

Anyone had this happen? I'm camping in Alaska having the joy of dealing if dealing with no trailer brakes b/c of this. My TT batteries also do no not charge while driving.

Ive read relays, frayed wires, bad grounds...circuit boards (eek). Anyone dealt with this? It's a 10' 1500 LT

 

[kbrunlees]

What is a DIC and what is a 10' 1500 LT? is that a truck, a trailer? If you are having issues with your trailer brakes, the most common problem, if you are running on dirt roads, is the wires going to the trailer brakes themselves. They get smashed off by the road gravel. Second is the Plug between the truck and trailer, depending on how old it is, they will eventually corrode and break. and the last thing generally is the fuses which for the trailers is in the cab, there are separate fuses for the trailer connections. I hope this helps.

 

[MiledOut]

your trailer brakes should continue to work with this on, unless its a wiring problem. and for it to charge your batteries youll need to hook up your power wires(under the hood by your fuse box, the 2 posts infront of it to be exact, the wires will be tapped around some of the harnesses.), if not done already, then it could be wiring, fuses, relays, etc. http://www.eworldz.com/truck/gmt900.pdf

 

[Highfly]

your trailer brakes should continue to work with this on, unless its a wiring problem. and for it to charge your batteries youll need to hook up your power wires(under the hood by your fuse box, the 2 posts infront of it to be exact, the wires will be tapped around some of the harnesses.), if not done already, then it could be wiring, fuses, relays, etc. http://www.eworldz.com/truck/gmt900.pdf

Are you sure about that wire?? The reason I ask is I had a 2010 and the wire was never connected. But I did have to take a shunt out and add a fuse in the fuse box so the trailer battery would charge. Edit, Found this on the web... http://www.dieselplace.com/forum/63...004-5-2005-lly/14802-trailer-wiring-12-v.html

 

[MiledOut]

Are you sure about that wire?? The reason I ask is I had a 2010 and the wire was never connected. But I did have to take a shut out and add a fuse in the fuse box so the trailer battery would charge.

what I had to do on mine and it works so im guessing it is right. but that is a 07 to a 10 could be different.

 

[Braddock54]

Are you sure about that wire?? The reason I ask is I had a 2010 and the wire was never connected. But I did have to take a shut out and add a fuse in the fuse box so the trailer battery would charge. Edit, Found this on the web... Trailer Wiring 12 V - Diesel Place : Chevrolet and GMC Diesel Truck Forums

bingo. This wire was either never connected or came disconnected. Also there was a short in the trailer brake controller and I needed a new 30 dollar switch. Problem seems to be solved. Yesterday with this error message I had zero trailer brakes. Not cool. Thanks for the replies guys.

 

[Highfly]

bingo. This wire was either never connected or came disconnected. Also there was a short in the trailer brake controller and I needed a new 30 dollar switch. Problem seems to be solved. Yesterday with this error message I had zero trailer brakes. Not cool. Thanks for the replies guys.

Curious does your truck have a factory tow package on it? I remember now it was my 2000 that I had to put the fuse in, it did not have a factory tow package on it. My 2010 had a tow package as does my new 2013. They did not require anything done to them for everything to work. Both my 2010 and my 2013 have the wire all tied up beside the fuse box but I have never needed to use them,???? Glad you got everything sorted out.

 

[medler]

I noticed the other day that my 08 chev doesn't have 12 V constant to the trailer plug.
That's the wire I am thinking you have to hook up (the one under the master cylinder )to get constant power to the plug. There's also one between the fender and fuse box This one is for power to a aftermarket brake controller . Both have eyelits on them. I have the built in brake controller as well in mine

Not sure why its not hooked up but I am also guessing that the trailer batteries won't charge as your driving if its not hooked up to


Sent from my phone

 

[medler]

So i hooked up that wire tonight and bam it has 12V constant to the plug now,,,so for anyone who has a new style GM,,you wont have trailer charging capabilities without that wire hooked up..Plus you have to add a fuse as well to the stud on fuse box under the hood

I noticed the other day that my 08 chev doesn't have 12 V constant to the trailer plug.
That's the wire I am thinking you have to hook up (the one under the master cylinder )to get constant power to the plug. There's also one between the fender and fuse box This one is for power to a aftermarket brake controller . Both have eyelits on them. I have the built in brake controller as well in mine

Not sure why its not hooked up but I am also guessing that the trailer batteries won't charge as your driving if its not hooked up to


Sent from my phone

 

[Highfly]

So i hooked up that wire tonight and bam it has 12V constant to the plug now,,,so for anyone who has a new style GM,,you wont have trailer charging capabilities without that wire hooked up..Plus you have to add a fuse as well to the stud on fuse box under the hood

Again I am curious, was your truck built with a factory tow package. If it was then I do not believe you need to do anything. I just checked my 2013 and it has 12 volts to the plug already..

 

[MiledOut]

Again I am curious, was your truck built with a factory tow package. If it was then I do not believe you need to do anything. I just checked my 2013 and it has 12 volts to the plug already..

From what ive read some dealers connect this or these wires for you.

 

[Highfly]

From what ive read some dealers connect this or these wires for you.

Both my 2010 and 2013 still had/have the wire beside the fuse box not connected?? As I mentioned the 2000 I had did not have the tow package and it did require to have the wire hooked up and a shunt removed and a fuse added. Would love to get this all figured out.

 

[Murminator]

We had a problem with a '12 3/4 gasser everytime we signalled right or brake lights came on the trailer brakes would slam on couldn't figure out end up cutting trailer brake wires... we were on our way to an emergency figure lights were more important than brakes on hiway driving turns out factory 7 pin on the truck when they installed it looks like they stretched it and pulled the wires a bit and bare wires touching I blamed the boss forgetting to unplug and driving away but it would have broken the factory housing so it must have happened when built

 

[tater]

I've had 3 chevy 3500s. All have had factory tow package and I've had to hook them all up.

 

[MiledOut]

Both my 2010 and 2013 still had/have the wire beside the fuse box not connected?? As I mentioned the 2000 I had did not have the tow package and it did require to have the wire hooked up and a shunt removed and a fuse added. Would love to get this all figured out.

well lets get to the bottom of this power comes from fuse 65(gas) or 61(diesel) and stud 2 according to the wiring diagram

 

[Braddock54]

Hey guys, mine is a 2010 half ton. It has the tow package. Sounds like not having trailer battery charging lead hooked up is common. The dealer also had to add the fuse for this to work. Would be nice if they dealt with all this from factory for the "tow package".

 

[medler]

Again I am curious, was your truck built with a factory tow package. If it was then I do not believe you need to do anything. I just checked my 2013 and it has 12 volts to the plug already..

Ya factory tow package. 3/4 ton 6.0L
Wire wasn't hooked up

And like I said the wire between LF fender an fuse box is for power for a aftermarket brake controller. As mine is the built in factory one


Sent from my phone

 

[medler]

Both my 2010 and 2013 still had/have the wire beside the fuse box not connected?? As I mentioned the 2000 I had did not have the tow package and it did require to have the wire hooked up and a shunt removed and a fuse added. Would love to get this all figured out.

Ya that wire is for a aftermarket brake controller.

The one under the master cylinder is the 12V constant. It must be hooked up to the smaller stud on the fuse box on my 08


Sent from my phone

 

[Highfly]

I went to the dealer today as I now have an engine light on since getting it back from getting all my hail damage repaired (maybe coincidence?) anyways I asked them about the wire, they didn't know so I demanded them to find out. They came back and said it must be hooked up and they will do that when the truck comes in for service. I said, no you wont cause I'm not paying for it. I bought a truck with a towing package that should have been ready to be used as a tow vehicle....... I'll hook it up myself...

 

[medler]

Ya. You would think any truck with tow package would have everything ready to go Not the case I guess


Sent from my phone