2008 Factory Trailer Brake Controller

1990ss · June 8, 2009

My '08 Silverado has the factory trailer brake controller. I've only pulled a trailer once and all the lights worked, but I had no trailer brakes. Put a test light on the plug on the truck and everything worked except the power and electric brakes.

Is there a fuse somewhere that needs to be installed? Has everyone else's worked right from the factory? I figured it would have been ready to go from the factory. Maybe it was a problem with the trailer?

Stevens03 · June 8, 2009

Do a search, you have to connect it under the hood in order for it to work from what I understand. There's been plenty of photo instructions on how to do it.

1990ss · June 8, 2009

I've tried searching, but really couldn't find any answers. Most of the topics I found were how to hook up an aftermarket controller. I've got the factory intergrated controller. Do I still need to connect wires under the hood to get the brakes to work?

bill190 · June 8, 2009

Does the brake controller look like this...

Or look like this...

1990ss · June 8, 2009

It looks like the first picture.

Bluedog · June 8, 2009

No, it should work without hooking anything up - however if you need 12V to the trailer for the brakes to work, you do need to hook up that wire under the hood. It is located under the master cylinder and is hooked up to the small stud under the fuse box cover. If you need help with this I will post the picture instructions.

Couple of questions: Is your trailer electric over hydraulic brakes? If so the IBC won't work without hooking up a couple of magnets in the brake circuit. Also, is the truck ignition off when you hook up the trailer? It needs to be so the computer will see the trailer. Also make sure the 7 way is seating all the way.

If none of these apply / help you need to see the dealer...

1990ss · June 8, 2009

Do I need power for the brakes to work? I don't think they're hydralic brakes. Also, with a test light on the electric brake pin on the connector in the bumper, and the brake controller lever pressed over, the test light will not light up.

Bluedog · June 8, 2009

And one more thing - the IBC won't show a brake signal with a tester. It has to be hooked up to a load to activate the system. Attached are the instructions for hooking up the 12v trailer power.

Installing_Auxiliary_12_Volt_Feed_to_Trailer.pdf

1990ss · June 8, 2009

Ok, well I don't think I need that wire. What's the wire between the fuse box and the fender? For an aftermarket controller?

pwall · June 8, 2009

<snip> Also, is the truck ignition off when you hook up the trailer? It needs to be so the computer will see the trailer. <snip>

Hmm...my '07 doesn't seem to need to be turned off. When I plug my trailer in with the truck running, the DIC will indicate 'TRAILER CONNECTED' and it works fine.

Perhaps the '08s are different.

Bluedog · June 9, 2009

Ok, well I don't think I need that wire. What's the wire between the fuse box and the fender? For an aftermarket controller?

Yes...

Bluedog · June 9, 2009

<snip> Also, is the truck ignition off when you hook up the trailer? It needs to be so the computer will see the trailer. <snip>

Hmm...my '07 doesn't seem to need to be turned off. When I plug my trailer in with the truck running, the DIC will indicate 'TRAILER CONNECTED' and it works fine.

Perhaps the '08s are different.

I can get away with not turning the ignition off about half the time. It will work everytime if I connect with the ignition off though.