ECD SYSTEM, Diagnostic DTC:P0545, P0546

DTC Code DTC Name
P0545 Exhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 1
P0546 Exhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 1

DESCRIPTION

The exhaust gas temperature sensors are installed before and after the NSC catalytic converter to sense the exhaust gas temperature.

A thermistor built into the sensor changes its resistance value according to the exhaust gas temperature. The lower the exhaust gas temperature, the greater the thermistor resistance value. The higher the exhaust gas temperature, the lower the thermistor resistance value.

The exhaust gas temperature sensor is connected to the ECM. The 5 V power source voltage in the ECM is applied to the exhaust gas temperature sensor from terminal THCI (for sensor 1) and THCO (for sensor 2) via resistor R.

The resistor R and the exhaust gas temperature sensor are connected in series. When the resistance value of the exhaust gas temperature sensor changes in accordance with changes in the exhaust gas temperature, the voltage at terminals THCI (for sensor 1) and THCO (for sensor 2) also changes.

DTC No. DTC Detection Condition Trouble Area
P0545

When exhaust gas temperature sensor (for sensor 1) value falls below minimum threshold for 0.6 seconds.

(3 trip detection logic)

  • Open or short in exhaust gas temperature sensor (for sensor 1) circuit

  • Exhaust gas temperature sensor (for sensor 1)

  • ECM
DTC No. DTC Detection Condition Trouble Area
P0546

When exhaust gas temperature sensor (for sensor 1) value exceeds maximum threshold for 0.6 seconds.

(3 trip detection logic)

  • Open or short in exhaust gas temperature sensor (for sensor 1) circuit

  • Exhaust gas temperature sensor (for sensor 1)

  • ECM
Related Data List
DTC No. Data List

P0545

P0546

 Exhaust Temperature B1S1

WIRING DIAGRAM

A004NN7E10
*a THEC
*b Exhaust Gas Temperature Sensor (for Sensor 1)

CAUTION / NOTICE / HINT

Note

When replacing the ECM, the ECM needs Registration and Initialization Click here.

Tech Tips


  • When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. Then after installing the new ECM, perform all of the initialization/registrations for the "Learning Values Write" function by following the instructions shown on the GTS display.

  • Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (EXHAUST GAS TEMPERATURE SENSOR (FOR SENSOR 1) - ECM)


    1. Disconnect the exhaust gas temperature sensor (for sensor 1) connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      B85-1 (THCI) - B91-92 (THCI) Always Below 1 Ω
      B85-2 (E2) - B91-91 (ETCI) Always Below 1 Ω
      B85-1 (THCI) or B91-92 (THCI) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

    OK

  2. INSPECT EXHAUST GAS TEMPERATURE SENSOR (FOR SENSOR 1)


    1. Inspect the exhaust gas temperature sensor (for sensor 1) Click here.


    NG

    REPLACE EXHAUST GAS TEMPERATURE SENSOR (FOR SENSOR 1) Click here

    OK

  3. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR


    1. Repair or replace the harness or connector.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  5. REPLACE EXHAUST GAS TEMPERATURE SENSOR (FOR SENSOR 1)


    1. Replace the exhaust gas temperature sensor (for sensor 1) Click here.


    NEXT

  6. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Clear the DTCs Click here.

    4. Turn the ignition switch off and wait for 60 seconds or more [A].

    5. Perform road test [B].

    6. Repeat [A] and [B] for the number of trips detected.

    7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    8. Confirm that the DTC is not output again.


    NEXT

    END