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DTC P0546 EXHAUST TEMPERATURE SENSOR CIRCUIT HIGH-BANK 1

DTC P0546 EXHAUST TEMPERATURE SENSOR CIRCUIT HIGH-BANK 1

DTC DETECTING CONDITION:


• Immediately at fault recognition

• GENERAL DESCRIPTION


TROUBLE SYMPTOM:


• Hard to start

• Erroneous idling

• Poor driving performance


Important

After repair or replacement of faulty parts, conduct Clear Memory Mode and Inspection Mode .


WIRING DIAGRAM:


CHECK CURRENT DATA.

Start the engine.

Read the data of exhaust temperature sensor signal using Vehicle Diagnostic Interface or OBD-II general scan tool.

Note
• Vehicle Diagnostic Interface

For detailed operation procedure, refer to the “READ CURRENT DATA FOR ENGINE”.

• OBD-II general scan tool

For detailed operation procedures, refer to the OBD-II General Scan Tool Instruction Manual.


Is the temperature less than 372°C (702°F)?

Yes


No

• Repair the poor contact.

•
Note

In this case, repair the following:

• Poor contact in exhaust temperature sensor

• Poor contact in ECM

• Poor contact in joint connector



CHECK HARNESS BETWEEN EXHAUST TEMPERATURE SENSOR AND ECM CONNECTOR.

Turn the ignition switch to OFF.

Disconnect the connector from exhaust temperature sensor.

Measure the voltage between exhaust temperature sensor connector and engine ground.

Connector & terminal

(B279) No. 1 (+) — Engine ground (−):

Is the voltage more than 10 V?

Yes

Repair the battery short circuit in harness between ECM and exhaust temperature sensor connector.


No


CHECK HARNESS BETWEEN EXHAUST TEMPERATURE SENSOR AND ECM CONNECTOR.

Turn the ignition switch to ON.

Measure the voltage between exhaust temperature sensor connector and engine ground.

Connector & terminal

(B279) No. 1 (+) — Engine ground (−):

Is the voltage more than 10 V?

Yes

Repair the battery short circuit in harness between ECM and exhaust temperature sensor connector.


No


CHECK HARNESS BETWEEN EXHAUST TEMPERATURE SENSOR AND ECM CONNECTOR.

Measure the voltage between exhaust temperature sensor connector and engine ground.

Connector & terminal

(B279) No. 1 (+) — Engine ground (−):

Is the voltage more than 4 V?

Yes


No

• Repair the harness and connector.

•
Note

In this case, repair the following:

• Open circuit in harness between ECM and exhaust temperature sensor connector

• Poor contact in exhaust temperature sensor connector

• Poor contact in ECM connector

• Poor contact in joint connector



CHECK HARNESS BETWEEN EXHAUST TEMPERATURE SENSOR AND ECM CONNECTOR.

Turn the ignition switch to OFF.

Measure the resistance of harness between exhaust temperature sensor connector and engine ground.

Connector & terminal

(B279) No. 2 — Engine ground:

Is the resistance less than 5 Ω?

Yes

Replace the exhaust temperature sensor.


No

• Repair the harness and connector.

•
Note

In this case, repair the following:

• Open circuit in harness between ECM and exhaust temperature sensor connector

• Poor contact in exhaust temperature sensor connector

• Poor contact in ECM connector

• Poor contact in joint connector