For 1990-2009 cars only
- Block the wheels.
- Apply the parking brake.
- Start the engine.
- Charge the system air pressure to the governor cut-out point.
- Check that the service brakes fully apply when depressing the brake pedal.
- Check that the brakes promptly release when the brake pedal is released. If the brakes are sluggish, check that air vents through the exhaust port (5) when releasing the brakes.
- If the brakes do not promptly release, repair or replace the valve (4).
- Remove the wheel blocks.
