Spring Brakes Check
Spring brakes will activate when air pressure drops between 25-45 PSI.
- Check manufacturer’s specifications for exact pressure.
- Continue depressing and releasing the brake from the low air pressure warning test.
Once air pressure reaches 25-45 PSI, the spring brakes activate.
- Parking brakes knob (yellow) will pop out on straight trucks.
- Trailer brakes knob (red) will also pop out on combination units with air brakes