How Does a Brake Controller Install on a 2021 Entegra Accolade?

Question:

I have a 2021 Entegra Accolade on the S2RV Freightliner chassis. I want to connect a Tekonsha Prodigy P2 to the wiring harness that is located under the kick plate on the drivers side. The harness does not have a connector, it just has 6 wires that are taped at the end with some abbreviated white stickers. The P2 has 4 wires, a white, blue, red, and black. Can you tell me which P2 wire goes to which wire on the wiring harness? Also, do I need a fuse somewhere in the line, or does the Freightliner wiring harness have one in it? Thanks for your help in advance.

asked by: Mr. T

Expert Reply:

Unless you can identify what the wires say on your 2021 Entegra Accolade, you're going to need to use a Circuit Tester like item # PTW2993 to find the correct ones that match up with your P2 Brake Controller item # 90885. Even though they are abbreviated you should be able to reference your owner's manual to decipher what their function is. This would save you a lot of time. You can also look that information up online you only need 4 of them.

White - Ground
Red - 12V Constant Power
Red/White - Brake Signal
Blue - Brake Controller Output

One of the wires should have power all the time. That would be the power source for the controller and would run to the black wire. One of the wires should have voltage only when the brakes are applied. That goes to the red wire of the controller. That leaves two wires. The brake output and the ground.

You will need to test for the ground wire. Ground the tester to the constant 12-volt power wire, then probe the remaining two wires. The wire that lights the tester will be the ground, and then you'll need to find the brake output circuit which should be a blue wire.

As far as a fuse goes the power wire in that bundle of wire should go to a fuse. If not you can add a 20-amp In-Line Circuit Breaker like item # 9506P. I have no way of knowing if you have one or not you'll have to trace the wire to the source.