Air Break Practice Test

Results

#1. How should you test your vehicle's low air pressure warning signal?

Pump the brakes while your ignition is off.

Repeatedly press and release the brake pedal to lower the air pressure to 207 kPa (30 psi).

Repeatedly press and release the brake pedal to lower the air pressure to 414 kPa (60 psi).

Manually let the air out of your brakes and see if the signal comes on.

Start the test with the pressure above 621 kPa (90 psi) and the ignition on. Then repeatedly press and release the brake pedal. In most vehicles, the low air pressure warning signal should come on when the pressure falls below 414 kPa (60 psi). If the warning device fails to activate at 414 kPa (60 psi), the low air pressure warning device is defective. You should never need to get down to 207 kPa (30 psi).