Checking the Low Coolant Level Indicator (VW Passat B3)

Depending on the model and version, VW PASSAT vehicles are equipped with a low coolant level indicator. For this purpose, a sensor is installed in the expansion tank.

Examination

The coolant level must be within the norm; top up if necessary.

Turn on the ignition, do not start the engine. The control lamp on the instrument panel should flash briefly and then go out. If the control lamp flashes continuously, disconnect the plug at the expansion tank sensor. Connect the plug contacts with a short jumper. If the control lamp has now gone out, replace the sensor.

Connect the plug to the expansion tank sensor. After a short time, the control lamp should flash.

If the indicator lamp does not flash, turn on the ignition. Remove the relay in position 5 of the central distribution device. The relay is marked with the number 43. Connect terminal 4/31 to terminal 36 on the relay block with a short jumper or, as a test, insert a new relay. Turn on the ignition. If the indicator lamp flashes, replace the relay. Otherwise, find the wire break using the electrical diagram.

(The article is posted on the portal: VWManual)