Vauxhall ASTRA Owner's Manual page 234

Control indicator u for ABS
It comes on for a few seconds after the
ignition is turned on. The system is ready
for operation when the control indicator
goes out.
If the control indicator does not go out
after a few seconds, or if it illuminates while
driving, there is a fault in the ABS. The
brake system remains operational without
ABS regulation.
Self-check
Each time the ignition is turned on and the
engine started, after moving away from a
speed of around (2 mph) 3 km/h the system
performs a self-check which may be
audible.
Fault
9
Warning
If there is a fault in ABS, the wheels may
be subject to locking due to braking that
is heavier than normal. The advantages
of ABS are no longer operational. The
vehicle can no longer be steered and may
swerve.
You can continue driving, provided you
drive with care and anticipation.
Brakes
Have the cause of the fault remedied. We
recommend that you consult your Vauxhall
Authorised Repairer. The system's
integrated self-diagnostics allows faults to
be quickly remedied.
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