Any success using GM brake controller option?

[Ditter]

I have a 2009 2500 ¾ ton diesel pickup with factory brake controller option.
The brake controller will not stop trailer at an idle roll with when manual brake switch is actuated.
Controller is set a gain of 10. I took AS to JC and they checked out brakes brake away worked OK took drums off and checked condition of breaks and checked for proper operation. Brake system reported OK.
When I plug in AS wire harness to truck TV dash indicates trailer connected. When I unplug AS dash indicator displays check trailer connection.
Has anybody had success using factory GM controller?
Do I need to install after market controller?

[exthemius]

I can't speak for the Chevy one...but I can say that when we first purchased our 71, I had to have the gain on my factory Ford all the way up to 10 to stop. We purchased a new hitch a few months back and had to replace the original umbilical cord with a new one, and the first time I hit the brakes everything locked up!

My point: you might want to check the cord, as apparently there was so much resistance in our original cord that now our gain is set to 6.5.

[moosetags]

We have a 2011 Chevrolet Silverado 3500 with the built-in factory trailer brake controller. It has worked flawlessly for us. I like it much better than our Tekonshas. We have both a prodigy and a P3, and like both very much.

From the data that you have provided, I agree that the most likely culprit is your Airstream's umbilical. The easiest way to diagnose your problem is to hook up to another trailer that has trailer brakes. Use the manual slide on the truck's trailer brake controller, and see if it will lock the brakes on the other trailer. If so, the problem is in the trailer's umbilical. If not, the problem is in the tow vehicle. Conversely, you can hook your Airstream to another tow vehicle, and see how that works.

Brian

[dznf0g]

Should work fine with drums...not discs. Check for high resistance like the previous posts say.

[Silver Otter]

All good advice above. Ours locks things up at 8.5.

[Ditter]

I Checked umbilical cord connection. Found cord was partially replaced. New cord was cut and connected in a splice box to old cord. Both old umbilical cord and brake leads went through a hole into AS floor near spare tire. Inside under sofa wires enter and then go into wall. Pulled white wire (ground) found it attached to ground bar in circuit breaker control box, blue wire went in same hole as white but could not find end when pulling, brake leads white went to ground bar black went into wall unable to find end.
I checked TV with VOM meter and verified voltage did fluctuate consistently to the degree of brake applied (6VDC to 13 VDC).
With trailer jacked up and brake controller gain set at 10, brake was applied lightly I could hear magnet coils hum but could rotate wheel, with ¾ brakes applied brakes tried to grip but I could still turn wheel, when full brakes was applied I could still rotate wheels with great difficulty.
With TV off I pulled the breakaway safety and was not able to turn jacked up wheels.
I looked at schematic that shows umbilical cord connection. Print shows the umbilical cord wires, white and blue are directly connected to brake leads along with the emergency brake switch supply’s 12V+ and trailer Battery - terminal. The manual mentioned an adjustable resistor that is in the brake circuit but it was not shown on print.
Inside trailer I pulled slack in both brake leads cutting each one separately. I marked each end and pulled slack wire out of hole. I installed crimp ring terminals to brake leads and attached each to appropriate studs in splice box (Blue and white).
After connections were completed I preformed a test
1st, on breakaway safety switch. I was unable to turn jacked up wheels. I Reinserted breakaway safety pin.
2nd Next test TV with umbilical cord connected and brake controller set at a gain of 5. TV brake were applied lightly, I could hear magnet coils hum had difficulty rotating wheels when pedal was depressed midway I could not rotate wheels.
Unable to test drive do to darkness but think this may have solved problem. Will try tonight
Dose any one know where this resistor is located?

[danlehosky]

We have a 2011 Tahoe with a factory brake controller. We have the gain set on 4 and it works very well.
Dan

[xrvr]

Do you still have to install the correct fuse under the hood on GM as in the past? jim

[Ridgerunner3]

Originally Posted by zigzagguzzi

Do you still have to install the correct fuse under the hood on GM as in the past? jim

If I remember correctly, on the GM trucks with a factory brake controller, you need to hook up a wire under the hood to provide battery power to the trailer. You do not need to hook the wire that gives you power to the brake controller as you do for GM trucks without the factory brake controller.

[AirsDream]

Sounds as if you found your problem. But if not, I'll note that I have a '08 GMC 3/4 ton diesel with the factory controller, and if I recall correctly, I needed to connect to the fuse box at two different terminals, a.) a line that supplied truck power to the trailer e.g. for charging the coach batteries a little bit while underway, and b.) a line that supplied power to the trailer brakes. You can learn more on the issue by doing some searching on www.thedieselpage.com

The service personnel at two different GM and Chevy truck dealerhsips were completely unhelpful / unknowledgeable about this issue.

[AL’ UM- MONEY]

I recently purchased a new 2011 GMC. The brake controller works great and it tows wonderfully. The previous post makes me think. I have not checked the power to the trailer and assumed every thing was set from the factory. If I disconnect the battery while attached to the TV and have lights then I should have charging current and a seven way plug properly working from the factory.

[Ditter]

Last night test was better; I could feel brakes slowing trailer but had gain set at 10. No wheel lock ups.
I did take truck back to dealer last week, they found 1 red wire not connected, they made connection and checked to make sure the 40 amp fused was installed.
Tonight after work a friend is bringing over his Ford super duty that is equipped with factory brake control that he knows works from towing his on trailer this will at least point me to problem vehicle.

[Ditter]

Ford super duty with known to be working brake controller provided same brake results poor to none. Made appointment at JC will post findings.
Next removed all umbilical cord connections and measured with OHM meter all = 0.0
At least the problem has been narrowed down to one.

[Ditter]

Brakes fixed
The problem was identified as drums were not turned when new back plates which included brake shoes and magnets were installed.
Mechanic showed me brake problem by inspecting wear patterns on new brakes.
(note AS had approximately 500 miles on new brakes)
· About 30% of brake linings were making contact with drums.
· 10% of magnets were making contact.
· The cause of weak brakes was attributed to drums not turned.
My observation on why brakes did not work properly.
The magnets are attracted to sides of drums, when this occurs brake force, depending on magnet current, is applied to brake linkage which extends brake shoes toward brake drums the faster the wheel turns the greater the grater the brake pressure until wheel lockup occurs. Lockup is controlled by using less gain on controller limiting current flow to magnets.
Magnets need surface area contact to work properly, similar to brake shoe linings. For optimal brake performance when replacing brake parts it is imperative to turn or replace drums to allow for proper seating of new components.
Thanks for all the help from forum