ECD SYSTEM(w/ Glow Plug Controller), Diagnostic DTC:P0545 and 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 NSR (NOx Storage Reduction) 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 powered by a 5 V supply from the THCI (B1S1) and THCO (B1S2) terminals of the ECM via resistor R.

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.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0545

Exhaust Gas Temperature Sensor Circuit Low (Bank 1 Sensor 1)

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

(2 trip detection logic)

  • Open or short in exhaust gas temperature sensor B1S1 circuit

  • Exhaust gas temperature sensor B1S1

  • ECM

Comes on

DTC stored

P0546

Exhaust Gas Temperature Sensor Circuit High (Bank 1 Sensor 1)

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

(2 trip detection logic)

  • Open or short in exhaust gas temperature sensor B1S1 circuit

  • Exhaust gas temperature sensor B1S1

  • ECM

Comes on

DTC stored
Table 1. DTC Detection Drive Pattern

DTC No.

DTC Detection Drive Pattern

P0545

Ignition switch ON for 2 seconds

P0546

Both of the following conditions are met for 2 seconds:

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

  • 11 minutes elapsed since engine started
Table 2. Related Data List

DTC No.

Data List

P0545

Exhaust Temperature B1S1

P0546
Tip:

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

Temperature Displayed

Malfunction

50°C (122°F) (engine warmed up)

Open circuit

950°C (1742°F)

Short circuit

WIRING DIAGRAM

A293327E10

CAUTION / NOTICE / HINT

Note:

When replacing the ECM, perform ECM Initialization and Registration.

Click here

Tip:

  • When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. Then after installing a new ECM, perform all of the initialization and registration procedures 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. READ VALUE USING GTS (EXHAUST TEMPERATURE B1S1)

    1. Connect the GTS to the DLC3.

    2. Start the engine.

    3. Turn the GTS on.

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

      Powertrain > Engine and ECT > Data List

      Tester Display

      Exhaust Temperature B1S1

    5. Read the value.

      Standard

      The exhaust gas temperature varies in accordance with the vehicle conditions.

      Result

      Result

      Proceed to

      50°C (122°F)

      A

      950°C (1742°F)

      B

      The exhaust gas temperature varies in accordance with the vehicle conditions

      C
      Tip:

      • Since the display range of the GTS is 50°C (122°F) or higher, temperatures less than 50°C (122°F) will not be displayed properly.

      • If the exhaust gas temperature changes, there is no open or short circuit.

      • If there is an open circuit, the GTS indicates 50°C (122°F) (engine warmed up).

      • If there is a short circuit, the GTS indicates 950°C (1742°F).

    B

    READ VALUE USING GTS (CHECK FOR SHORT IN WIRE HARNESS)Click here

    C

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

    A

  2. READ VALUE USING GTS (CHECK FOR OPEN IN WIRE HARNESS)

    A200286C02

    *1

    Exhaust Gas Temperature Sensor B1S1

    *2

    ECM

    *a

    Front view of wire harness connector

    (to Exhaust Gas Temperature Sensor B1S1)

    1. Disconnect the exhaust gas temperature sensor B1S1 connector.

    2. Connect terminals B136-1 (THCI) and B136-2 (E2) of the exhaust gas temperature sensor B1S1 connector on the wire harness side.

    3. Connect the GTS to the DLC3.

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

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

      Powertrain > Engine and ECT > Data List

      Tester Display

      Exhaust Temperature B1S1

    6. Read the value.

      Standard

      950°C (1742°F)

    Result

    Proceed to

    OK

    NG
    OK

    CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE EXHAUST GAS TEMPERATURE SENSOR B1S1Click here

    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

      Tester Connection

      Condition

      Specified Condition

      B136-1 (THCI) - B212-124 (THCI)

      Always

      Below 1 Ω

      B136-2 (E2) - B212-125 (ETCI)

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTORClick here

    OK

  4. CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM

    1. Replace the ECM.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

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

    1. Replace the exhaust gas temperature sensor B1S1.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  6. READ VALUE USING GTS (CHECK FOR SHORT IN WIRE HARNESS)

    1. A200307C15

      *1

      Exhaust Gas Temperature Sensor B1S1

      *2

      ECM

      Disconnect the exhaust gas temperature sensor B1S1 connector.

    2. Connect the GTS to the DLC3.

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

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

      Powertrain > Engine and ECT > Data List

      Tester Display

      Exhaust Temperature B1S1

    5. Read the value.

      Standard

      50°C (122°F)

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE EXHAUST GAS TEMPERATURE SENSOR B1S1Click here

    NG

  7. 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

      Tester Connection

      Condition

      Specified Condition

      B136-1 (THCI) or B212-124 (THCI) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTORClick here

    OK

  8. REPLACE ECM

    1. Replace the ECM.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  9. REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  10. REPLACE EXHAUST GAS TEMPERATURE SENSOR B1S1

    1. Replace the exhaust gas temperature sensor B1S1.

      Click here

    Result

    Proceed to

    NEXT
    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIREDClick here

  11. 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.

      Powertrain > Engine and ECT > Clear DTCs

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

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

    6. Start the engine and allow it to idle until the engine coolant temperature is 80°C (176°F) or higher.

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

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

    9. Confirm that the pending DTC is not output again.

      Powertrain > Engine and ECT > Trouble Codes

    Result

    Proceed to

    NEXT
    NEXT

    END