Volkswagen Passat W8, Service Manual, Page: 34 / 52

34
Convenience and safety electronics
Interior monitor and anti-theft alarm system
The Passat W8 anti-theft alarm system is
equipped with a new function and a new alarm
horn. The new alarm horn, designated the H12, is
mounted in the plenum chamber. It has a
separate power supply.
The horn communicates bidirectionally with the
convenience system control unit J393. After the
car is locked, the horn is armed via the control
unit. This means the vehicle power supply and
the horn signalling line are monitored in addition
to the other functions of the anti-theft alarm
system. When the car is unlocked by the radio-wave
remote control key, the anti-theft alarm system is
deactivated. If the car is opened mechanically
via the lock cylinder of the door, the ignition must
be turned on within 15 seconds. If this does not
happen, the anti-theft alarm system is activated.
Function
Two lithium batteries integrated in the horn
ensure that the horn operates independent of the
car battery. The batteries have a life of approx. 5
to 7 years. If the batteries are discharged or
defective, the horn must be replaced.
Alarm horn H12
Fitting location
The convenience system
S261_047