200 Quattro Wagon L5-2226cc 2.22L SOHC Turbo (MC) (1989)
Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection
Temperature Safety Switch (Multi Function Temperature Sensor)
Temperature Sensor (Overheat Sensor - Multi Function)
There is no test procedure for this device, however there are distinct noticeable symptoms when it has failed. These symptoms are:
1.
Engine temperature gauge becomes inoperative.
2.
No boost pressure from turbocharger even though engine is NOT overheated.
3.
Climate control shuts off (no A/C for no apparent reason) even though system is fully charged and engine is NOT overheated.
This device, affectionately referred to by many Audi trained mechanics as the "multi-malfunction sensor", is reported to have a particularly high
mortality rate. If the engine control system has a problem that seems to be related to an overheated engine, yet the engine is not overheating, replace this
sensor.