Brake Controller Setup + First Drive Checks
A properly set brake controller improves braking performance, stability, and safety. This guide covers a simple setup approach and the first-drive checks we recommend for Mars caravan owners.
Note: Brake controller models differ. Use your controller manual for exact button names.
What a brake controller does
The brake controller tells the caravan brakes how much braking to apply when you brake the tow vehicle. Too little = the van pushes the car. Too much = the van brakes too aggressively.
Initial setup (simple method)
- Find a safe, flat area with room to stop (quiet road/industrial area).
- Set the controller gain/output to a low-to-mid starting point.
- Accelerate to a low speed (e.g., slow suburban speed) and apply brakes gently.
- If the van feels like it’s pushing the vehicle, increase gain slightly.
- If the van grabs or feels harsh, reduce gain slightly.
- Repeat small adjustments until stopping feels smooth and controlled.
Manual override test (if your controller has it)
Many controllers have a manual override lever/button that applies trailer brakes without vehicle brakes. Used correctly, it helps confirm trailer brakes are responding.
- At very low speed, apply manual override gently.
- You should feel the van braking.
- If you feel nothing, check the trailer plug connection and controller settings.
First drive checks (highly recommended)
After the first 10–20km (or after towing changes)
- Pull over safely and do a quick walkaround.
- Check tyres visually for any issues.
- Check for unusual heat around hubs/brakes (carefully).
- Confirm breakaway cable is secure and plug connection is still seated.
Listen and feel
- Any new vibrations, pulling, or instability should be investigated early.
- If braking feels inconsistent, re-adjust gain slightly and re-test.
Common causes of poor braking feel
- Incorrect gain setting
- Loose trailer plug connection
- Wet/dirty brake components after storage or water crossings
- Overloading or poor weight distribution
- Brake controller not calibrated (some models need initial calibration)
When to stop and contact support
- Brakes feel weak even with gain increased
- Brakes grab harshly and cannot be tuned out
- Trailer plug gets hot or shows scorch marks
- You notice smoke, burning smell, or excessive heat at hubs/brakes
What to include in a support ticket (if needed)
- Mars model + year
- Tow vehicle make/model
- Brake controller brand/model
- Description of braking feel (pushing, grabbing, inconsistent)
- Photos of trailer plug and any warning signs (heat/scorching)
- Short video of controller behaviour if relevant