AUDI A4 1995 B5 / 1.G AFC Engine Coolant Temperature Sensor Checking Workshop Manual

28-25


Engine Coolant Temperature
(ECT) sensor, checking

Notes:

To functionally check the Engine Coolant
Temperature (ECT) sensor Repair Group 01,
Read measuring value block, display group
001, display field 1.

Component locations page 28
-1 .

- Disconnect ECT sensor harness connector.

- Switch Fluke 83 multimeter to resistance range and measure between
ECT sensor terminals 1 (signal) and 3 (GND).

Specified values:
At approx. 20 C (68 F): approx. 2500 At approx. 80 C (176 F): approx. 330
Pa
ge 1 of 3 En
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perature
(ECT
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If the specified value is not obtained:
If the specified value is obtained: - Replace ECT sensor.
- Check wiring between ECT sensor and ECM as follows:
- Connect VAG 1598/19 test box to ECM harness connector page 01
-
255
.
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ge 2 of 3 En
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perature
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28-26


If the specified values are not obtained: - Check wiring for continuity between terminal 3 of ECT sensor harness
connector and engine Ground (GND).

Specified value: max. 1 - Check signal wire for continuity between ECT sensor harness
connector terminal 1 and test box socket 16A.

Specified value: max. 1 - Check both wires for short circuit to each other.

If wiring is OK and the ECT sensor is OK: - Eliminate short or open circuit in wiring between ECT sensor and ECM
connector -A- or engine Ground (GND).
ECT sensor terminal
number ECM Connector A or engine Ground
(GND)
1 16A
3 Engine Ground (GND)
- Replace the ECM page 01
-265
.
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ge 3 of 3 En
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perature
(ECT
) sensor, checkin
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