Installation of a Tekonsha P3 Brake Controller on a 2020 Mercedes Metris with Tow Package

Question:

I have a Tekonsha P3 brake controller. I have a 2020 Mercedes Metris with the factory tow package including the 7 pin electrical plug that I am installing on. I need to know what the current draw is for the stop light switch circuit on the controller and if that circuit needs to be fused and if so what amperage rating for the fuse. Thanks for any help you can provide.

asked by: Ray D

Expert Reply:

The stop light switch (red wire) on the Tekonsha Prodigy P3 Trailer Brake Controller # 90195 will use 12 volts. The stop light switch is not providing power or sending power, it is merely a switch that when it receives power indicates the controller to activate the brakes. The stop light switch circuit is not going to need a fuse. Because you already have the tow package on your 2020 Mercedes Metris you can use 10 Gauge Primary Wire (sold by the foot) # 10-1-1 which will run from your 7-way to your brake controller and Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers # 5506 to get power to the brake controller. The Hopkins Trailer Wiring Installation Kit # HM51010 is available if you do not already have the necessary tools and connectors.

I have also included a help article about wiring a brake controller you can take a look at for more information.

expert reply by: Scott S