Opel COMBO Owner's Manual page 135

A warning chime is also sounded
briefly if a fault is present when
reverse gear is engaged 3 95.
Note
The volume of the warning chime
can also be adjusted via the Driver
Information Centre 3 90.
Important hints for using the
parking assist systems
9 Warning
Under certain circumstances,
various reflective surfaces on
objects or clothing as well as
external noise sources may cause
the system to fail to detect
obstacles.
Special attention has to be paid to
low obstacles which can damage
the lower part of the bumper. If
such obstacles leave the detection
area of the sensors during
approach of the vehicle, a
continuous warning tone will
sound.
Caution
Performance of the sensor can be
reduced when sensors are
covered, e.g. by ice or snow.
Performance of the parking assist
systems can be reduced due to
heavy loading.
Special conditions apply if there
are taller vehicles involved (e.g.
off-road vehicles, mini vans,
vans). Object identification in the
upper part of these vehicles
cannot be guaranteed.
Objects with a very small reflection
cross section, like objects of
narrow size or soft materials, may
not be detected by the system.
Parking assist will not avoid a
collision with objects which are out
of the detection range of the
sensors.
Note
The parking assist system
automatically detects factory-fitted
towing equipment. It is deactivated
when the connector is plugged in.
Driving and operating
The sensor may detect a non-
existent object (echo disturbance)
caused by external acoustic or
mechanical disturbances.
133