Brakes Engage On Grand Design Momentum While Hooked Up To Shore Power

Updated 03/07/2019 | Published 03/06/2019

Question:

2016 grand design momentum 350m Just installed new electric brakes I am parked unplugged from truck. But 50 amp service is plugged in. when i reconnect wires to the brakes it engages them. Question should they engage when parked and plug into city power?

asked by: Jeffery G

Expert Reply:

The shore power circuit for your trailer should not have anything to do with the trailer's brakes as they are on completely different circuits and use an entirely different type of current (AC vs. DC). However, if you have a short on the AC power circuit and the circuit is sending power to the trailer frame/body which is commonly referred to as "Hot Skin" then that could then cause the brakes to engage via the ground wire. Therefore, I recommend you disconnect shore power and see if the brakes release. If they do then you will need to take your trailer to a service center to have it serviced.

If the brakes stay engaged when you are no longer hooked up to shore power then most likely there is a short between the brake output wire and the 12 volt power circuit on your trailer. The brake output wire would then need to be traced from each assembly up to the trailer connector in order to find the short. If you cannot find the short then the wire can be replaced with part # 10-1-1 (per foot). If you have any corrosion inside the trailer connector or there are loose wires behind it then that could also cause an issue for you.

Please note that this could also be a feature of your trailer but I have not heard of this before and was not able to reference it online so it may be wise to call the manufacturer with your VIN to check.

expert reply by: Conner L