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Home >> Audi >> 1987 >> 5000CS Turbo L5-2226cc 2.22L SOHC Turbo (MC) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Coolant Temperature Sensor/Switch (For Computer) >> Testing and Inspection >> Coolant Temperature Signal, Checking
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Coolant Temperature Signal, Checking


Coolant temperature sensor, checking

Test conditions
^ coolant temperature min. 20°C (68°F)

Work sequence





- Remove connector from coolant temperature sensor (arrow)
- Connect ohmmeter between coolant temperature sensor and ground cable
^ Specification: 60 ohm - 1 K ohm

If specification NOT OK
- Replace coolant temperature sensor

If specification OK
- Check sensor wiring
- Remove control unit cover located in passenger side footwell and unplug control unit connector





- Connect ohmmeter between contact 10 on control unit connector A and disconnected wire from coolant temperature sensor
^ Specification: approx. 0 ohm

If specification OK
- Check for open circuit in wiring

If circuit OK
- Replace control unit

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