On a steep downhill gradient the speed limiter's engine braking effect may be inadequate and the selected maximum speed is exceeded. The driver is alerted about this with an acoustic signal.
The signal is active until the driver has slowed to below the selected maximum speed.
The alarm is only activated after 5 seconds if the speed has been exceeded by at least 3 km/h (approx. 2 mph), provided that neither of the or buttons has been depressed during the last half minute.