Viper 550HF, Owner'S Manual

13

© 1997 Directed Electronics, Inc.

Diagnostics

The microprocessor at the heart of your system is constantly monitoring all of
the switches and sensors connected to it. It detects any faulty switches and
sensors and prevents them from disabling the entire system. The micro-
processor will also record and report any triggers that occurred during your
absence.

Arming Diagnostics

If the system is armed with an input active (door open, sensor triggering, etc.)
the unit will chirp once when arming and then one more time a few seconds
later. This is called 

Bypass Notification.

NOTE: Bypass notification will not occur when using Silent Mode

™

or if chirps have been pro-

grammed OFF.

The system will ignore the input that was active when it was armed until it
goes away. Three seconds later it will monitor that input normally. For exam-
ple, if your car has interior light exit delay, and you arm the system before the
interior light goes out, you may get Bypass Notification. Three seconds after
the light goes out, however, the doors are monitored normally.

Disarming Diagnostics

Extra disarm chirps are the 

Tamper Alert.

If four chirps are heard when dis-

arming, the system was triggered in your absence. If five chirps are heard, a
zone was triggered so many times that Nuisance Prevention Circuitry

™

has

bypassed that zone. In either case, the Status LED will indicate which zone
was involved (see Table of Zones section). The system will retain this informa-
tion in its memory, and chirp four or five times each time it is disarmed, until
the next time the ignition key is turned on.