Service Warning System

The oxygen sensor is surveillanced by a service warning system. Every 30,000 miles or 50,000 kms a warning light 'OXYGEN SENSOR' comes on at the dashboard, indicating the emission control system needs maintenance. The oxygen sensor must be renewed.

The service interval switch is interconnected to the speedometer drive cable and located at the left-hand engine carrier. After renewing the oxygen sensor, the service interval switch must be re-opened. For this, remove the plug at the lower side of the service interval switch and press a pin into the hole. On '5' and '7' series vehicles, the service interval switch is integrated in the instrument panel. With this construction, the bulb in the check control panel must be removed and discarded to extinguish the indicator light.