The HydraStar wiring diagram come in the box with the HydraStar unit. Units should be installed by an auto-electrician. 

Some common mistakes during installation of HydraStar unit

• The power (black) wire from the car's battery to the car's socket in pin no. 2 (reverse) must be at least a 6mm gauge wire.
• The same gauge wire (6mm), must be used from the trailer plug pin no. 2 to the HydraStar.
• The brake (blue) wire from the brake controller to the car's socket in pin no. 5 (service brakes) must be at least a 5mm gauge wire.
• The same gauge wire (5mm) must be used from the trailer plug pin no. 5 to the HydraStar.
• The black and blue wires in the 7 core trailer wire are not heavy enough a gauge wire to power the unit properly.

 We sell a range of trailer wire by the metre. 

Check your in car controller is compatible with the HydraStar unit here.