Description of on-Board Diagnostics

General Information
- The ultrasonic interior monitoring system supplements the anti-theft alarm and detects unauthorized entry into the vehicle by way of the side windows and causes the anti-theft alarm to be triggered.
- The vehicle doors are still scanned by way of door contact switches.
- The interior monitoring system control module has a DTC memory, but it is not possible to perform On Board Diagnostic (OBD) with the scan tool V.A.G 1551.
- If required the interior monitoring system from 07.95 can be deactivated by way of a momentary contact switch. Deactivation is cancelled automatically on next locking operation.

Function
The ultrasound interior monitoring system consists of:
- Control module for ultrasound sensors -J347
- Ultrasonic sensor left for ATW -G170
- Ultrasonic sensor right for ATW -G171
- Switch for interior monitoring system -E183

The ultrasonic sensors in the upper part of the left-hand and right-hand B-pillar trim scanning the side windows and transmit scanning signals to the ultrasonic sensors control module.

If the scanning signal changes, the ultrasonic sensors control module triggers the alarm via the anti-theft alarm control module.

The interior monitoring system control switch actuates the warning lamp in the fog taillight switch. This lamp permits interior monitoring system diagnostic.