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 CCo 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 (B1S1) and THCO (B1S2) 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 (B1S1) and THCO (B1S2) also changes.

P0545
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
Ignition switch ON for 2 seconds

Exhaust gas temperature sensor B1S1 output voltage is 0.15 V or less.

(1 trip detection logic)


  • Open or short in exhaust gas temperature sensor B1S1 circuit

  • Exhaust gas temperature sensor B1S1

  • ECM

P0546
DTC Detection Drive Pattern DTC Detection Condition Trouble Area

Both of following conditions are met for 2 seconds:


  • Engine coolant temperature is 80°C (176°F) or more.

  • 11 minutes elapsed after engine start.

Exhaust gas temperature sensor B1S1 output voltage is 3.28 V or more.

(1 trip detection logic)


  • Open or short in exhaust gas temperature sensor B1S1 circuit

  • Exhaust gas temperature sensor B1S1

  • ECM

Related Data List
DTC No. Data List
P0545 Exhaust Temperature B1S1
P0546

Tech Tips

When DTC P0545 or P0546 is stored, check the exhaust gas temperature by entering the following menus on the intelligent tester: Powertrain / Engine and ECT / Data List / Exhaust Temperature B1S1.

Temperature Displayed Malfunction
20°C (68°F) Open circuit
900°C (1652°F) Short circuit

WIRING DIAGRAM

A005I06E01
*a EXHAUST GAS TEMPERATURE SENSOR B1S1

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 intelligent tester. 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 tester display.

  • Read freeze frame data using the intelligent tester. 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. READ VALUE USING INTELLIGENT TESTER (EXHAUST TEMPERATURE B1S1)


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and warm it up.

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Exhaust Temperature B1S1.

    5. Read the value.

      Standard
      Same as the actual exhaust gas temperature (50 to 700°C [122 to 1292°F] during idling after warm-up).
      Result
      Result Proceed to
      20°C (68°F) A
      900°C (1652°F) B
      Same as the actual exhaust gas temperature (50 to 700°C [122 to 1292°F] during idling after warm-up) C

      Tech Tips


      • If there is an open circuit, the intelligent tester indicates 20°C (68°F).

      • If there is a short circuit, the intelligent tester indicates 900°C (1652°F).


    B
    C
    A
  2. READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS)


    1. A005GT0E02
      Text in Illustration
      *1 Exhaust Gas Temperature Sensor B1S1
      *a

      Front view of wire harness connector

      (to Exhaust Gas Temperature Sensor B1S1)

      Disconnect the exhaust gas temperature sensor B1S1 connector.

    2. Connect terminals THCI and ETCI of the exhaust gas temperature sensor (B1S1) wire harness side connector.

    3. Connect the intelligent tester to the DLC3.

    4. Turn the ignition switch to ON and turn the tester on.

    5. Enter the following menus: Powertrain / Engine and ECT / Data List / Exhaust Temperature B1S1.

    6. Read the value.

      Standard
      900°C (1652°F)
    7. Reconnect the exhaust gas temperature sensor connector.


    OK
    NG
  3. CHECK HARNESS AND CONNECTOR (EXHAUST GAS TEMPERATURE SENSOR B1S1 - ECM)


    1. Disconnect the exhaust gas temperature sensor B1S1 connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      B40-1 (THCI) - A59-50 (THCI) Always Below 1 Ω
      B40-2 (E2) - A59-51 (ETCI) Always Below 1 Ω
    4. Reconnect the exhaust gas temperature sensor connector.

    5. Reconnect the ECM connector.


    OK
    NG
  4. READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS)


    1. A005MCKE32
      Text in Illustration
      *1 Exhaust Gas Temperature Sensor B1S1

      Disconnect the exhaust gas temperature sensor B1S1 connector.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON and turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Exhaust Temperature B1S1.

    5. Read the value.

      Standard
      20°C (68°F)
    6. Reconnect the exhaust gas temperature sensor connector.


    OK
    NG
  5. CHECK HARNESS AND CONNECTOR (EXHAUST GAS TEMPERATURE SENSOR B1S1 - ECM)


    1. Disconnect the exhaust gas temperature sensor B1S1 connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      B40-1 (THCI) or A59-50 (THCI) - Body ground Always 10 kΩ or higher
    4. Reconnect the exhaust gas temperature sensor B1S1 connector.

    5. Reconnect the ECM connector.


    NG
    OK
  6. REPLACE ECM


    1. Replace the ECM Click here.


    NEXT
  7. CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE EXHAUST GAS TEMPERATURE SENSOR B1S1


    1. Replace the exhaust gas temperature sensor B1S1 Click here.


    NEXT
  8. REPAIR OR REPLACE HARNESS OR CONNECTOR


    NEXT
  9. CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM


    1. Replace the ECM Click here.


    NEXT
  10. REPLACE EXHAUST GAS TEMPERATURE SENSOR B1S1


    1. Replace the exhaust gas temperature sensor B1S1 Click here.


    NEXT
  11. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Connect the intelligent tester to the DLC3.

    2. Clear the DTCs Click here.

    3. Turn the ignition switch off and wait for 30 seconds or more.

    4. Turn the ignition switch to ON and wait for 10 seconds or more.

    5. Start the engine and wait until the engine coolant temperature is 80°C (176°F) or more.

    6. Confirm that 11 minutes or more elapsed after engine was started.

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

    8. Confirm that the DTC is not output again.


    NEXT