Is Relay Needed with P2 or P3 Brake Controller When Installed with Electric Over Hydraulic Actuator

Question:

I am currently looking at a trailer with the dexter brake system installed on it. I have already looked into getting a tekonsha p2 or p3 brake controller for the system but after talking to a few people who have used trailers with the same brake system and brake controllers, they state that they have also wired a 30amp relay into the system for some reason. After doing my own research I can not come up with a reason why they have done this. Can you possibly give me an idea what this may control? And also whether or not I would just be good to use the trailer with the p2 or p3 brake controller? The truck is a 1996 dodge 3500 with the brake control wiring already installed. Thanks!

asked by: James O

Expert Reply:

No additional relay is needed when you install a P2 part # 90885 or P3 part # 90195 in your truck to use it with an electric over hydraulic actuator.

You just need to put either controller in hydraulic mode and you'll be good.

expert reply by: Jameson C