Honda CLARITY Plug-In Hybrid 2020 Owner's Manual page 418

uuWhen DrivinguAdaptive Cruise Control (ACC) with Low Speed Follow
In the following cases, a buzzer sounds, ACC with Low Speed Follow is deactivated,
and the message Cruise Cancelled: Slope Too Steep. Watch Downhill Speed
appears in the driver information interface.
• While descending a long slope and the vehicle has repeatedly applied the brakes
to maintain the set speed.
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