How to Install a Trailer Brake Box
- 1). Identify a location for the trailer bake box within easy reach of the driver's normal position, where the unit can be aligned with the front-rear axis of the vehicle and be within 30-degrees of horizontal. Use the fasteners supplied with the brake box to fit its support bracket in the desired location.
- 2). Connect the four wires of the trailer brake box harness to power sources as directed by the manufacturer's installation instructions. Typically, the color-coded wires should be attached as follows: white wire to ground, blue wire to terminal two of the seven-pin tow hitch, red wire to the switched side of the brake pedal micro-switch and black wire to a 12-volt hot supply via an in-line fuse.
- 3). Fit the terminal multi-block at the end of the trailer brake box harness into the receiver built into either the rear or underside of the unit.
- 4). Use plastic cable ties to secure all wire runs so that they cannot interrupt free access to the control pedals and do not contact hot or moving components.
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