Parking Brake Control Switch

The switch with the yellow diamond-shaped icon operates the parking brake. See Fig. , item 3. Pulling the parking brake switch applies the tractor spring parking brakes. For the park brakes to be released, the parking brake switch must be pushed, the air pressure must be at least 100 psi (690 kPa), the keyswitch must be ON, and the service brake pedal must be pressed.

The LED indicator in the switch illuminates when the park brake is set, blinks when the park brake is released and the air supply system is pressurizing but not yet ready, and extinguishes when the park brake is released and the system has enough pressure.

If the trailer is not equipped with spring parking brakes, pull the parking brake switch to apply the tractor parking brakes and the trailer service brakes.