Fuses on RV and Toad Blow After Installing InvisiBrake and Connecting to RV
Updated 11/16/2016 | Published 11/15/2016
Question:
Hello I have installed a Invisibrake in a 2007 Dodge Dakota. Toad. The tow vehicle is a 2007 Fleetwood 31M Terra. I wired a 7 pin harness to both vehicles to include a chassis ground, 12vdc line and the brake monitor installed in the dash of the Motorhome. The neg. bat. cable is disconnected on the toad when in tow, so I have wired the 12vdc from the mh to power the intellibrake and the aux. brake switch for the monitor. I also realized that if the toad became separated from the mh I would lose power to everything including the breakaway switch. So I wired the toad battery directly to the 12vdc from the mh so that the intellibrake controller would have power in case of a breakaway. I also believed this would charge the toad battery. Here is the problem when I hooked up the harness between the mh and toad, it blew a 20amp fuse in the 12vdc line at the toad battery as well as the running lite fuse 15amp in the mh. I have checked for shorts and wiring alignment and found no problems. Could the problem be a surge when plugging in the harness or can I not hook the 12vdc from the mh to the toad battery? I bought some 20amp resettable fuses just in case. I appreciate all your expert help - thank you.
asked by: George R
Helpful Expert Reply:
I believe the issue is in how you have the InvisiBrake # RM-8700 wired up. It has a very specific wiring set up that needs to be followed. I have included a picture of what that should be.
It sounds like you have a trickle charge coming from both the running light circuit and the 12 volt circuit, whether intentional or not, and that is overloading the system. You would only need one of those charge lines to the vehicle battery. If you re-adjust how the unit is wired to match the diagram that should solve the problem.

Product Page this Question was Asked From
Roadmaster InvisiBrake Flat Tow Brake System - Preset
- Flat Tow Brake System
- Brake Systems
- Pre-Set System
- One-Time Setup
- Vehicle Battery
- Fixed System
- Power Assist Brake Compatible
- Air Brakes
- Hydraulic Brakes
- Indicator Lights
- Roadmaster
more information >
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