Cabrio GLX L4-2.0L (ABA) (2001)
Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection
Engine Coolant Temperature (ECT) Sensor -G62-, Checking
Special tools and equipment
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VAG 1551 Scan Tool or VAG 1552 with cable
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VAG 1551/3
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Test box VAG 1598/22
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Hand multimeter VAG 1526 or multimeter VAG 1715
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Adapter set VAG 1594
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Wiring diagram
NOTE: The engine control module will use the intake air temperature as a replacement value for an engine start (start temperature replacement value)
as soon as there is a malfunction stored in the DTC memory, which affects the engine coolant temperature (ECT) sensor -G62-. The temperature then
rises according to a model stored in the control module. When the engine has reached normal working temperature a fixed replacement value will be
displayed after a certain period. This fixed value is also dependent upon the intake air temperature.
Test conditions
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Engine must be cold.
Test sequence
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Connect VAG 1551 Scan Tool ((VAG 1552). Then switch ignition on and select engine control module with "Address word" 01.(Connecting scan
tool and selecting engine control module See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Reading and
Clearing Diagnostic Trouble Codes/Scan Tool Connecting/With Manufacturer's Scan Tool/Connecting VAG Scan Tool 1551/1552).
Indicated on display
Rapid data transfer
HELP
Select function XX
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Press keys 0 and 8 for function "Read Measuring Value Block" and confirm entry with Q key.
Indicated on display
Read Measuring Value Block
HELP
Input display group number XX
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Press keys 0, 0 and 4 for "Display group number 4" and confirm entry with Q key.
Indicated on display: (1 to 4 Display zones)
Read Measuring Value Block 4
->
1
2
3
4
If the specification is not obtained:
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Read off coolant temperature value in display zone 3.
Specification: approx. coolant temperature
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Perform check according to following table:
Display1)
Cause
Approx. -46 degree C
Open circuit or short to positive
Approx. 141 degree C
Short to Ground
1) If a temperature is displayed which deviates greatly from the ambient temperature of the sensor, check sensor wiring for transfer resistances.
If the specification is obtained:
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Start engine and run at idle speed. Temperature value must increase uniformly.
NOTE:
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Temperature rises in steps of 1.5 degree C.
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If irregular engine running occurs in certain temperature ranges and the temperature figure does not increase without interruption, the temperature
signal is temporarily interrupted and the sensor must be replaced.
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Press -> key.
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Press keys 0 and 6 for function "End Output" and confirm entry with Q key.