General Knowledge · Antilock Braking Systems
How should a driver apply the brakes on a vehicle equipped with ABS?
1.Apply steady, firm pressure and let the system pulse the brakes automatically; do not pump the pedalCorrect answer
2.Pump the brake pedal rapidly, the same way as on a vehicle that has no ABS installed
3.Apply and fully release the pedal once every second or so, timed manually by the driver
4.Use only the trailer hand valve and never the foot brake, whatever the road speed
Explanation
With ABS, the correct technique is to apply steady, firm pressure and let the system itself modulate each wheel's braking; pumping the pedal defeats that modulation and is the technique associated with older, non-ABS brakes. 49 CFR 383.111(a)(3)(ii) names the emergency braking-procedure knowledge area but not this specific technique, so it is standard driver-training content, attributed to the manual. The wrong options each substitute a manual pumping or partial-braking pattern, or avoid the foot brake altogether, all of which work against how ABS is designed to be used.
Source: 49 CFR 383.111(a)(3)(ii)
Related Antilock Braking Systems questions
- Under federal regulation, which of these vehicles must have antilock brakes (ABS) installed?
- What does federal regulation require of trailers manufactured on or after March 1, 1998, regarding antilock brakes?
- What does antilock braking system (ABS) actually do for a driver?
- If a vehicle's ABS malfunction lamp stays on after starting the engine, what should the driver do?