Coolant Temperature Sensor/Switch Testing for A4 Cabriolet (2005)
-
Disconnect Engine Coolant Temperature (ECT) sensor connector at -G2- / -G62- (arrow).
-
Connect multimeter between terminals C and D of sensor to measure resistance.
Range A shows resistance values for temperature range 0...50 degree C and range B shows the values for temperature range 50...100 degree C.
Sample readings:
-
30 degree C corresponds to a resistance of 1500 to 2000 Ohms
-
80 degree C corresponds to a resistance of 275 to 375 Ohms
If specified value is not obtained:
-
Replace Engine Coolant Temperature (ECT) sensor -G62-.
If specified value is obtained:
-
Connect test box V.A.G 1598/31 to wiring harness for ECM; do not connect directly to ECM. See: Powertrain Management/Computers and
Control Systems/Testing and Inspection/Scan Tool Testing and Procedures/Scan Tool Testing/With Generic Scan Tool/Scan Tool
Connecting/Test Box, Connecting For Wiring and Component Test