90CS Quattro V6-2.8L (AAH) (1994)
Temperature Gauge: Testing and Inspection
Engine Coolant Temperature (ECT) gauge, checking
Electronic thermoswitch connections
+ voltage supply, terminal 15a
C to overheat warning lamp
R to A/C control unit
T to coolant temperature gauge
The thermal switch -F76- is located on the coolant line behind the right-side cylinder head.
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Disconnect thermal switch connector.
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Set digital multimeter (Fluke 83 or equivalent) to voltage measuring range.
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Connect multimeter between thermal switch connector terminal T and Ground (GND), using VW 1594 connector test kit.
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Switch ignition on.
Specification: 9.8-10.4 volts
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Switch ignition off.
If voltage is not as specified:
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Check wiring for open circuit according to wiring diagram, and repair as necessary.
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Check voltage stabilizer. See: Instrument Cluster/Instrument Panel Voltage Regulator/Testing and Inspection
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Connect VW 1301 instrument/gauge tester between thermal switch connector terminal -T- and Ground (GND), using VW1594 connector test kit.
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Adjust VW 1301 to setting of 560.
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Switch ignition on.