Faulty Signal - Permanent Fault

ECM-2000 ENGINE COOLANT TEMPERATURE (ECT) SENSOR
FAULTY SIGNAL - INTERMITTENT FAULT

Checking engine coolant temperature (ECT)



- Fault-tracing must begin with cold engine (+20° C (68° F)) so that the engine coolant temperature (ECT) sensor can be tested over as wide a temperature range as possible.
- Turn off climate control
- Start the engine.

Read off engine coolant temperature (ECT).
Check that the engine coolant temperature (ECT) is within its permitted range and corresponds with the engine warming up.

Is the temperature within its permitted range?
Yes - Continue below.
No - Skip to "Replacing Engine Coolant Temperature (ECT) sensor"

Checking thermostat



- Start the engine and run it until the engine coolant temperature (ECT) reaches approximately 100°C (212°F).
- Activate engine cooling fan (FC) with engine running.
- Wait approximately 90 seconds and then shut-off engine cooling fan (FC)

Read off engine coolant temperature (ECT). If it is 85°C (185°F) or lower when the fan stops, the thermostat is defective.

Is the temperature 85°C (185°F) or lower when the fan stops?
Yes - Continue below.
No - Test Complete


Replacing Thermostat



Replace the thermostat, Thermostat, Checking/Replacing


Replacing Engine Coolant Temperature (ECT) sensor



Replace engine coolant temperature (ECT) sensor according to Engine Temperature Sensor, Replacing


Verification



Hint: After carrying out the repair, check that the fault has been remedied.

- Fault-tracing must begin with cold engine (+20°C (68°F)) so that the engine coolant temperature (ECT) sensor can be tested over as wide a temperature range as possible.
- Ignition off.
- Reconnect connectors, reinstall components
- Start the engine.
- Read off the temperature.

Check that the engine coolant temperature (ECT) is within its permitted range and corresponds with the engine warming up.

Is the temperature within its permitted range?
Yes - Testing Complete.
No - Continue below.


Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed. Exit fault tracing for this diagnostic trouble code (DTC) or make another attempt.