Horse Trailer Brakes Are Not Aggressive Enough Using P2 Brake Controller on 2013 Toyota Tundra

Question:

We have a 2013 Toyota Tundra V8 5.7L. We installed the Tekonsha P2 brake controller and went to a parking lot to set the voltage level. We were hauling a two horse bumper pull trailer with 5foot dressing room empty weight is right around 3,000 pounds. We got the tow vehicle up to 25 and applied the trailer brakes with controller set to 6. The tires did not lock up. This was the case until the controller was set at 12. We are thinking that the brakes should have locked up earlier than this. We have not been able to find a chart or anything that indicates what the setting usually is for a set up like this. Could you please provide some information?

asked by: Kristine M

Expert Reply:

It is going to be different on every trailer because there are several factors, not just the controller, that lead to braking performance. You will want to make sure that the trailer brakes are properly adjusted. You will want there to be a slight but constant drag of the pad on the drum when you turn the wheel. I have linked a video to the right in which our installer adjusts the brakes. Go to about the 4 minute mark to view the process.

If you adjust the brakes and still do not get proper braking performance then there are some other things to look at. Disconnect the trailer and use a multimeter, # PT89ZR if you need an inexpensive one, to test the voltage output on the brake circuit on the vehicle side trailer connector.

Set the controller to full power and have someone sit in the truck and fully apply the manual override on the controller. The multimeter should read approximately 12 volts. If it does not then there is some issue between the controller and trailer connector on the brake circuit wire you will need to track down. It is also possible that if the controller is tilted or turned to one side it will not function properly. Make sure the controller is mounted properly according to the instructions.

If it does show the proper voltage then plug in the trailer and test again behind the trailers connector. Then test again at the brake magnet power wires. Any significant voltage drop indicates a possible break in the wiring that will need to be fixed. A slight voltage drop is normal due to the distance the electricity has to travel (resistance).

While testing also inspect the magnet wiring for any breaks. Also make sure the magnet ground wires, trailer and vehicle side ground wires, are all attached to clean and corrosion free bare metal surfaces. Make sure that the vehicle and trailer side connectors are clean and free of corrosion inside and out.

Visually inspect the magnets and if you can see the copper windings coming through the magnets will need to be replaced. To further test the magnets you can follow the FAQ article that I have linked. I have also included a link to our FAQ article on troubleshooting brake controllers.

expert reply by: Michael H