How to Install Tekonsha P3 Trailer Brake Controller on Thor Vegas Class A Motorhome

Question:

I would like to install a brake controller Tekonsha P3 but THOR said I cant just plug it in since they installed the 7 way plug what are my options for installing the controller?

asked by: Chris

Expert Reply:

The Tekonsha Prodigy P3 Trailer Brake Controller # 90195 referenced in your question can definitely still be installed on your Thor Vegas Class A Motorhome, even though it does not have the factory plug and play harness installed.

Based on my research, it looks like your motorhome is built on a Ford E-450 chassis. As you have already found out, we have been told that Thor has removed the dash and the Ford installed electrical connections that would have allowed for the brake controller to be installed using a plug-in harness.

The first thing you will need to install is a 4-pole flat wiring harness in your coach. I recommend using the 7-Pole and 4-Pole Trailer Connector Sockets w/ Mounting Bracket and Wiring - Vehicle End # HM40975-11998, which actually gives you a 7-way and a 4-way. This will allow you to tap into the coach's lighting wiring to install the 4-pole trailer connector. You will also need a small tester like # PTW2993 that will help you find the correct wires for each lighting function. I have attached the installation details and a video demonstration of the kit for you to look at.

With the motorhome's length, you may need additional wiring # 10-2-1 to reach the necessary distance.

Lastly, you will just need to use the wiring plug that comes included with the Prodigy P3 to complete the connection.

The Tekonsha Prodigy P3 is a great proportional brake controller that will activate your trailer's brakes at the same time and with the same intensity that you apply to them in your motorhome. It features an easy-to-read LCD display with continuous diagnostics to alert you to any potential issues. This particular unit is well known for its reliability and ease of installation.

I have attached a couple of video reviews of the products mentioned as well as a couple of articles on brake controller installation and wiring that you may find helpful.