LOW ENGINE COOLANT TEMPERATURE INDICATOR LIGHT/HIGH ENGINE COOLANT TEMPERATURE WARNING LIGHT ILLUMINATES OR FLASHES CONTINUOUSLY [INSTRUMENT CLUSTER]

id0903d5013300

Possible cause

• ECT sensor malfunction

• Instrument cluster malfunction

Diagnostic Procedure

Step

Inspection

Action

1

PERFORM CAN MALFUNCTION DIAGNOSIS AND DTC INSPECTION

•  Perform the CAN malfunction diagnosis according to the recommendation of FOREWORD [INSTRUMENT CLUSTER] malfunction diagnosis, and if there is no CAN malfunction, perform inspection for DTCs.
(See DTC INSPECTION [INSTRUMENT CLUSTER].)

•  Is the DTC displayed?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [INSTRUMENT CLUSTER].)

No

Go to the next step.

2

VERIFY THE MALFUNCTION SYMPTOM

•  Cool down the engine.

•  When the ignition is switched ON, does the engine coolant temperature warning light illuminate or flash?

Yes

Go to Step 4.

No

Go to the next step.

3

VERIFY ILLUMINATION OF LOW ENGINE COOLANT TEMPERATURE INDICATOR LIGHT

•  Switch the ignition ON (engine on).

•  Monitor the PID ECT using the M-MDS.

•  Verify that the low engine coolant temperature indicator light illuminates when the ECT monitor value is 55 °C {131 °F} or more (SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5, MZR 1.6) / 40 °C {104 °F} or more (SKYACTIV-D 1.5, SKYACTIV-D 2.2).

•  Does the low engine coolant temperature indicator light illuminate?

Yes

Go to the next step.

No

The system is operating normally.

4

INSPECT ECT SENSOR

•  Inspect the ECT sensor.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-D 1.5].)

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-D 2.2].)

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [MZR 1.6].)

•  Is the ECT sensor normal?

Yes

Replace the instrument cluster.

(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)

No

Replace the ECT sensor.

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)

(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [MZR 1.6].)

Step	Inspection	Action
1	PERFORM CAN MALFUNCTION DIAGNOSIS AND DTC INSPECTION • Perform the CAN malfunction diagnosis according to the recommendation of FOREWORD [INSTRUMENT CLUSTER] malfunction diagnosis, and if there is no CAN malfunction, perform inspection for DTCs. (See DTC INSPECTION [INSTRUMENT CLUSTER].) • Is the DTC displayed?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [INSTRUMENT CLUSTER].)
1		No	Go to the next step.
2	VERIFY THE MALFUNCTION SYMPTOM • Cool down the engine. • When the ignition is switched ON, does the engine coolant temperature warning light illuminate or flash?	Yes	Go to Step 4.
2		No	Go to the next step.
3	VERIFY ILLUMINATION OF LOW ENGINE COOLANT TEMPERATURE INDICATOR LIGHT • Switch the ignition ON (engine on). • Monitor the PID ECT using the M-MDS. • Verify that the low engine coolant temperature indicator light illuminates when the ECT monitor value is 55 °C {131 °F} or more (SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5, MZR 1.6) / 40 °C {104 °F} or more (SKYACTIV-D 1.5, SKYACTIV-D 2.2). • Does the low engine coolant temperature indicator light illuminate?	Yes	Go to the next step.
3		No	The system is operating normally.
4	INSPECT ECT SENSOR • Inspect the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-D 1.5].) (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-D 2.2].) (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [MZR 1.6].) • Is the ECT sensor normal?	Yes	Replace the instrument cluster. (See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)
4		No	Replace the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 1.5].) (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2].) (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [MZR 1.6].)