Honda Backup Sensors 08V67-SHJ-1000-81 Owner's Manual page 7

The sensors detect the closest rear obstacle.
In this example, the corner
sensor detects the side wall.
The sensors may not detect the rear bumper of tall
vehicles.
© 2004 American Honda Motor Co., Inc. - All Rights Reserved.
How the Backup Sensors Work
When towing a trailer, the audible signal may keep
sounding if the shift lever is moved to the reverse
position. When this occurs, turn the backup sensor
switch OFF.
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