Contents Section: Cooling Fan All sections

Engine Cooling Fan Audi 90 B4

Cooling Fan 1 illustration ~132 words

DESCRIPTION

All 90 and 100 models are equipped with an electronic cooling fan. The cooling fan is operated by a thermoswitch in response to engine temperature. Cooling fan thermoswitch is located on coolant pipe behind right cylinder head. (Scheme 1)

BELT ADJUSTMENT

Application(1) Deflection - In. (mm)
90 & 100.2-.4 (5-10)
(1) Deflection is measured with moderate thumb pressure applied midway on longest belt run.
(1)Deflection is measured with moderate thumb pressure applied midway on longest belt run.

BELT ADJUSTMENT

TROUBLE SHOOTING

Note. No trouble shooting information is available from manufacturer.

Engine Coolant Temperature (ECT) Sensor

Disconnect ECT sensor connector located at rear of left cylinder head, on coolant pipe. Measure resistance between ECT sensor terminals. If resistance is not as specified, replace ECT sensor. See ECT SENSOR RESISTANCE table. If resistance is as specified, check wiring. If wiring is okay, replace ECU.

TemperatureOhms
68°F (20°C)Approximately 2500
176°F (80°C)Approximately 330

ECT SENSOR RESISTANCE

Scheme 1

Scheme 1

COOLING SYSTEM SPECIFICATIONS

ModelSpecification
Coolant Replacement Interval30,000 Miles
Coolant Capacity12.0 Qts. (11.0L)
Thermostat Opens188°F (87°C)

COOLING SYSTEM SPECIFICATIONS

WIRING DIAGRAMS

See appropriate chassis wiring diagram in WIRING DIAGRAMS article.