1Gd-Ftv Engine Control. Dtc P0545 Exhaust Gas Temperature Sensor Circuit Low (Bank 1 Sensor 1)

The exhaust gas temperature sensors are installed before and after the DPF 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 higher 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 THCF, THCI and THCO 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 the exhaust gas temperature, the voltage at terminals THTO, THCI and THCO also changes. The exhaust gas temperature sensor monitors the temperature upstream of the DOC catalyst. The No. 2 exhaust gas temperature sensor monitors the temperature upstream of the DPF catalyst. The No. 3 exhaust gas temperature sensor monitors the rise in temperature of the DPF catalyst. When PM forced regeneration is needed, the ECM operates the exhaust fuel addition injector to obtain target upstream temperature of the DPF catalytic converter as monitored through sensor 2. In addition, the ECM monitors the temperature increase of the DPF catalytic converter using sensor 3.

P0545
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Idle the engine for 3 seconds after warming up the engine (the engine coolant temperature is 60°C (140°F) or higher) and allowing 11 minutes to elapse after starting the engine.	Exhaust gas temperature sensor output voltage is below 0.2 V for 3 seconds or more when all conditions are met. (1 trip detection logic): After starting the engine, 11 minutes or more elapses Engine is running Coolant temperature is 60°C (140°F) or more	Open or short in exhaust gas temperature sensor circuit Exhaust gas temperature sensor ECM

P0546
DTC Detection Drive Pattern	DTC Detection Condition	Trouble Area
Idle the engine for 3 seconds after warming up the engine (the engine coolant temperature is 60°C (140°F) or higher) and allowing 11 minutes to elapse after starting the engine.	Exhaust gas temperature sensor output voltage is higher than 4.95 V for 3 seconds or more when all conditions are met. (1 trip detection logic): After starting the engine, 11 minutes or more elapses Engine is running Coolant temperature is 60°C (140°F) or more	Open or short in exhaust gas temperature sensor circuit Exhaust gas temperature sensor ECM

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

HINT:

DTC P20CF (Exhaust fuel addition injector malfunction) may be stored if there is an open malfunction in an exhaust gas temperature sensor circuit.
Sensor 1 represents the sensor located upstream of the DOC catalytic converter.
When DTC P0545 or P0546 is output, check the exhaust gas temperature indicated by "Powertrain / Engine and ECT / Exhaust Temperature B1S1" using the GTS.

Reference:
Condition	Exhaust Temperature B1S1	Exhaust Gas Temperature Sensor Condition
Idling after warm-up	Constant at between 50 and 700°C (122 and 1292°F)	Normal
	-40°C (-40°F)	Open circuit
	1000°C (1832°F) or higher	Short circuit

MONITOR DESCRIPTION

The ECM constantly monitors the output voltages from the exhaust gas temperature sensors in order to detect problems with the sensors. When the sensor output voltage deviates from the normal operating range (between 0.2 V and 4.95 V) for more than 3 seconds after the engine is warmed up, the ECM interprets this as malfunction of the sensor circuit and illuminates the MIL.

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

After replacing the ECM, the new ECM needs registration (LandCruiser RM0000012XK0AUX.html) and initialization (LandCruiser RM000000TIN08HX.html).

HINT:

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.

1.READ VALUE USING GTS (EXHAUST TEMPERATURE B1S1)

Connect the GTS to the DLC3.

Turn the engine switch on (IG) and turn the GTS on.

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

Read the value.

Standard:: Same as the actual exhaust gas temperature (50 to 700°C [122 to 1292°F] during idling after warm-up), and varies after an engine speed of 3000 rpm is maintained for 1 minute.

Result
Temperature Displayed	Proceed to
-40°C (-40°F) (After warming up the engine)	A
1000°C (1832°F) or higher	B
OK: Same as the actual exhaust gas temperature (50 to 700°C [122 to 1292°F] during idling after warm-up), and varies after maintaining an engine speed of 3000 rpm for 1 minute after accelerating the engine from idling to 3000 rpm	C

HINT:

If there is a short circuit, the GTS will indicate -40°C (-40°F).
If there is an open circuit, the GTS will indicate 1000°C (1832°F) or higher.

Go to step 6

Go to step 11

A

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

Disconnect the exhaust gas temperature sensor connector.

Connect terminals 1 (E2) and 2 (THC3) of the exhaust gas temperature sensor wire harness side connector.

Connect the GTS to the DLC3.

Turn the engine switch on (IG) and turn the GTS on.

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

Read the value.
Standard:
1000°C (1832°F) or higher
Text in Illustration
*1
Exhaust Gas Temperature Sensor
*2
ECM
*a
Front view of wire harness connector
(to Exhaust Gas Temperature Sensor)

Text in Illustration
*1	Exhaust Gas Temperature Sensor
*2	ECM
*a	Front view of wire harness connector (to Exhaust Gas Temperature Sensor)

Reconnect the exhaust gas temperature sensor connector.

Go to step 4

OK

3.REPLACE EXHAUST GAS TEMPERATURE SENSOR

Replace the exhaust gas temperature sensor (LandCruiser RM000005UK3000X.html).

Go to step 11

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

Disconnect the exhaust gas temperature sensor connector.

Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection
Condition
Specified Condition
C169-2 (THC3) - C149-23 (THTO)
Always
Below 1 Ω
C169-1 (E2) - C149-22 (ETTO)
Always
Below 1 Ω

Reconnect the exhaust gas temperature sensor connector.

Reconnect the ECM connector.

Go to step 10

OK

5.REPLACE ECM

Replace the ECM (LandCruiser RM0000013Z002DX.html).

Go to step 11

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

Disconnect the exhaust gas temperature sensor connector.

Connect the GTS to the DLC3.

Turn the engine switch on (IG) and turn the GTS on.

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

Read the value.
Standard:
-40°C (-40°F)

Reconnect the exhaust gas temperature sensor connector.
Text in Illustration
*1
Exhaust Gas Temperature Sensor
*2
ECM

Text in Illustration
*1	Exhaust Gas Temperature Sensor
*2	ECM

Reconnect the exhaust gas temperature sensor connector.

Go to step 8

OK

7.REPLACE EXHAUST GAS TEMPERATURE SENSOR

Replace the exhaust gas temperature sensor (LandCruiser RM000005UK3000X.html).

Go to step 11

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

Disconnect the exhaust gas temperature sensor connector.

Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection
Condition
Specified Condition
C169-2 (THC3) or C149-23 (THTO) - Body ground and other terminals
Always
10 kΩ or higher

Reconnect the exhaust gas temperature sensor connector.

Reconnect the ECM connector.

Go to step 10

OK

9.REPLACE ECM

Replace the ECM (LandCruiser RM0000013Z002DX.html).

Go to step 11

10.REPAIR OR REPLACE HARNESS OR CONNECTOR

Repair or replace the harness or connector.

NEXT

11.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

Connect the GTS to the DLC3.

Clear the DTCs (LandCruiser RM000000PDK1E5X.html).

Start the engine.

Idle the engine for 3 seconds or more after warming up the engine (the engine coolant temperature is 60°C (140°F) or higher) and allowing 11 minutes to elapse after starting the engine.

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

Confirm that the DTC is not output again.

END

Tester Connection	Condition	Specified Condition
C169-2 (THC3) - C149-23 (THTO)	Always	Below 1 Ω
C169-1 (E2) - C149-22 (ETTO)	Always	Below 1 Ω