Tips on wiring the HydraStar Brake Actuator
Some common mistakes to avoid during installation of the HydraStar unit such as wire size.
The HydraStar wiring diagram comes in the box with the HydraStar unit. Units should be installed by an auto-electrician.
HydraStar is used for electric over hydraulic trailer brakes where the tow vehicle brake controller sends an electric signal to a hydraulic brake actuator on the trailer.
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.
These points are common because a trailer plug can look correctly connected while the cable size is still wrong for the actuator. A HydraStar unit needs the correct supply, brake signal and earth path to work as intended.
We sell a range of trailer wire by the metre.
Check your in car controller is compatible with the HydraStar unit here.
How electric over hydraulic trailer brakes work
Electric over hydraulic trailer brakes use an in-car brake controller to trigger a hydraulic actuator on the trailer. The actuator then pressurises the hydraulic brake system, instead of the brake controller directly powering electric drum brake magnets.
This is why wiring quality matters. The actuator depends on suitable power supply wiring, a compatible brake controller signal, correct trailer plug wiring for electric brakes and a sound hydraulic brake system.
Electric hydraulic boat trailer brakes are common because hydraulic trailer brakes are often used around marine trailers. The electrical side still needs the same care as any electric over hydraulic trailer brake installation in Australia.
Pre-wiring checks before fitting HydraStar
Read the HydraStar wiring diagram supplied with the unit before installation. Do not rely only on a generic trailer plug diagram or wire colours already present on the trailer.
|
Check |
Why it matters |
|---|---|
|
Brake controller compatibility |
The in-car controller must suit HydraStar operation before the actuator is wired. |
|
Cable gauge |
Undersized black or blue wiring can stop the unit from receiving the power or brake signal it needs. |
|
Trailer plug condition |
Loose pins, corrosion and poor earth connections can create intermittent actuator faults. |
|
Circuit protection |
Battery feeds and controller circuits should be wired with suitable protection by an auto-electrician. |
|
Hydraulic brake condition |
The actuator cannot correct worn, damaged or incorrectly adjusted hydraulic brake components. |
If the tow vehicle already has a brake controller, confirm it is suitable for an electric over hydraulic trailer brake controller setup before connecting the HydraStar.
Common symptoms to check
If the trailer brakes are weak, delayed or inconsistent, check the simple wiring and compatibility items before replacing major parts. Start with the trailer plug, socket, earth, cable gauge and controller settings.
If the actuator runs but braking is poor, the fault may be hydraulic rather than electrical. Check trailer brake components, brake fluid condition and manufacturer service requirements through a qualified mechanic or brake specialist.
If the actuator does not run, do not bridge wires or bypass protection to force operation. Test the power supply, brake signal and earth with the correct equipment, or use an auto-electrician.
Related parts and articles
For tow vehicle control, browse brake controllers and read our Brake Controller wiring diagram.
For trailer-side braking parts, browse trailer brakes and check the brake type fitted to the trailer before ordering.
For plug and socket reference, use our Trailer plug wiring diagram with the HydraStar instructions supplied in the box.
For hydraulic hose information, browse HydraLine brake lines where compatible replacement brake hoses are required.
Safety and specification notes
HydraStar wiring should follow the manufacturer's supplied diagram, the trailer manufacturer's requirements and applicable ADR, state or territory requirements. Trailer Spares Direct sells parts and does not engineer trailers.
Use a qualified auto-electrician for the tow vehicle wiring and brake controller setup. Use a qualified mechanic or brake specialist for hydraulic brake work, bleeding and fault diagnosis.
Still unsure which HydraStar wiring, brake controller or trailer brake part suits your trailer? Please call our friendly sales team on 07 3205 8846, email us or visit our store at 4 Leanne Crescent Lawnton.