1Gr-Fe Engine Control. Dtc P0136 Oxygen Sensor Circuit (Bank 1 Sensor 2)

A three-way catalyst converter is used in order to convert the carbon monoxide, hydrocarbons and nitrogen oxide into less harmful substances. To allow the three-way catalytic converter to function effectively, it is necessary to keep the air fuel ratio of the engine near the stoichiometric air fuel ratio. For the purpose of helping the ECM to deliver accurate air fuel ratio control, a heated oxygen sensor is used.
The heated oxygen sensor is located behind the three-way catalytic converter, and detects the oxygen concentration in the exhaust gas. Since the sensor is integrated with the heater that heats the sensing portion, it is possible to detect the oxygen concentration even when the intake air volume is low (the exhaust gas temperature is low).
When the air fuel ratio becomes lean, the oxygen concentration in the exhaust gas is rich. The heated oxygen sensor informs the ECM that the post-three way catalytic converter air fuel ratio is lean (low voltage, i.e. below 0.45 V).
Conversely, when the air fuel ratio is richer than the stoichiometric air fuel level, the oxygen concentration in the exhaust gas becomes lean. The heated oxygen sensor informs the ECM that the post-three way catalytic converter air fuel ratio is rich (high voltage, i.e. higher than 0.45 V). The heated oxygen sensor has the property of changing its output voltage drastically when the air fuel ratio is close to the stoichiometric level.
The ECM uses the supplementary information from the heated oxygen sensor to determine whether the air fuel ratio after the three-way catalytic converter is rich or lean, and adjusts the fuel injection time accordingly. Thus, if the heated oxygen sensor is working improperly due to internal malfunctions, the ECM is unable to compensate for deviations in the primary air fuel ratio control.

Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.1Gr-Fe Engine Control.Sfi System.
Dtc
P0136 Oxygen Sensor Circuit (Bank 1 Sensor 2)

DTC No.	DTC Detection Condition	Trouble Area
P0136 P0156	Abnormal voltage output: During active air fuel ratio control, conditions (a) and (b) are met for a certain period of time (2 trip detection logic): The heated oxygen sensor voltage does not decrease to below 0.21 V. The heated oxygen sensor voltage does not increase to higher than 0.59 V.	Open or short in heated oxygen sensor (bank 1, 2 sensor 2) circuit Heated oxygen sensor (bank 1, 2 sensor 2) Heated oxygen sensor heater (bank 1, 2 sensor 2) Air fuel ratio sensor (bank 1, 2 sensor 1) Gas leak from exhaust system
P0137 P0157	Low voltage (open): During active air fuel ratio control, conditions (a) and (b) are met for a certain period of time (2 trip detection logic): The heated oxygen sensor voltage output is below 0.21 V. The target air fuel ratio is rich.	Open in heated oxygen sensor (bank 1, 2 sensor 2) circuit Heated oxygen sensor (bank 1, 2 sensor 2) Heated oxygen sensor heater (bank 1, 2 sensor 2) Gas leak from exhaust system
P0138 P0158	High voltage (short): During active air fuel ratio control, conditions (a) and (b) are met for a certain period of time (2 trip detection logic): The heated oxygen sensor voltage output is 0.59 V or higher. The target air fuel ratio is lean.	Short in heated oxygen sensor (bank 1, 2 sensor 2) circuit Heated oxygen sensor (bank 1, 2 sensor 2) Air fuel ratio sensor (bank 1, 2 sensor 1) ECM

WIRING DIAGRAM

for Automatic Transmission

for Manual Transmission

CONFIRMATION DRIVING PATTERN

Connect the GTS to the DLC3.
Clear the DTCs.
Turn the engine switch off.
Turn the engine switch on (IG) and turn the GTS on (Step "A").
Warm-up the engine until the engine coolant temperature is 75°C (167°F) or more (Step "B").
With the transmission in 4th gear or more, drive the vehicle at 60 to 120 km/h (37 to 75 mph) for 10 minutes or more (Step "C").
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input DTCs: P0136, P0137, P0138, P0156, P0157 and P0158.

Check the DTC judgment result (Step "D").

GTS Display	Description
NORMAL	DTC judgment completed System normal
ABNORMAL	DTC judgment completed System abnormal
INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions
N/A	Unable to perform DTC judgment Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

Check that STATUS is NORMAL. If STATUS is INCOMPLETE or N/A, perform the driving pattern adding the vehicle speed and using the second gear to decelerate the vehicle.

INSPECTION PROCEDURE

HINT:

Malfunctioning areas can be identified by performing the Control the Injection Volume for air fuel ratio sensor function provided in the Active Test. The Control the Injection Volume for air fuel ratio sensor function can help to determine whether the air fuel ratio sensor, heated oxygen sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the Control the Injection Volume for air fuel ratio sensor operation using the GTS.

Connect the GTS to the DLC3.
Start the engine and turn the GTS on.
Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.
Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).
Monitor the output voltages of the air fuel ratio sensor and heated oxygen sensor (AFS Voltage B1S1 and O2S B1S2, or AFS Voltage B2S1 and O2S B2S2) displayed on the GTS.

HINT:

The Control the Injection Volume for air fuel ratio sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 12.5%.
Each sensor reacts in accordance with increases and decreases in the fuel injection volume.

GTS Display (Sensor)	Injection Volume	Status	Voltage
AFS Voltage B1S1 or AFS Voltage B2S1 (Air fuel ratio sensor)	+12.5%	Rich	Below 3.1 V
AFS Voltage B1S1 or AFS Voltage B2S1 (Air fuel ratio sensor)	-12.5%	Lean	Higher than 3.4 V
O2S B1S2 or O2S B2S2 (Heated oxygen sensor)	+12.5%	Rich	Higher than 0.55 V
O2S B1S2 or O2S B2S2 (Heated oxygen sensor)	-12.5%	Lean	Below 0.4 V

NOTICE:

The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.

Case	Air fuel ratio sensor (Sensor 1) Output Voltage	Heated oxygen sensor (Sensor 2) Output Voltage	Main Suspected Trouble Area
1			-
2			Air fuel ratio sensor Air fuel ratio sensor heater Air fuel ratio sensor circuit
3			Heated oxygen sensor Heated oxygen sensor heater Heated oxygen sensor circuit
4			Fuel injector assembly Fuel pressure Gas leakage from exhaust system (air fuel ratio extremely rich or lean)

Following the Control the Injection Volume for air fuel ratio sensor procedure enables technicians to check and graph the voltage outputs of both the air fuel ratio sensor and heated oxygen sensors.
To display the graph, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor / A/F Control System / AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2.

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, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

1.READ OUTPUT DTC (DTC P0136, P0137, P0138, P0156, P0157 OR P0158)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

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

Read DTCs.
Result
Result
Proceed to
P0138 or P0158
A
P0137 or P0157
B
P0136 or P0156
C

Go to step 9

Go to step 7

A

2.READ VALUE USING GTS (OUTPUT VOLTAGE OF HEATED OXYGEN SENSOR)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Data List / A/F Control System / O2S B1S2 or O2S B2S2.

Allow the engine to idle.

Read the heated oxygen sensor output voltage while idling.
Result
Result
Proceed to
Higher than 1.0 V
A
Below 1.0 V
B

Go to step 5

A

3.INSPECT HEATED OXYGEN SENSOR (CHECK FOR SHORT)

Disconnect the heated oxygen sensor connector.

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

Standard Resistance (Bank 1 Sensor 2):

Tester Connection	Condition	Specified Condition
2 (+B) - 4 (E2)	20°C (68°F)	10 kΩ or higher
2 (+B) - 3 (OX1B)	Always	10 kΩ or higher

Standard Resistance (Bank 2 Sensor 2):

Tester Connection	Condition	Specified Condition
2 (+B) - 4 (E2)	20°C (68°F)	10 kΩ or higher
2 (+B) - 3 (OX2B)	Always	10 kΩ or higher

Text in Illustration
*A	for Automatic Transmission
*B	for Manual Transmission
*a	Component without harness connected (to Heated Oxygen Sensor Bank 1)
*b	Component without harness connected (to Heated Oxygen Sensor Bank 2)
*c	Component without harness connected (to Heated Oxygen Sensor Bank 2)

Reconnect the heated oxygen sensor connector.

REPLACE HEATED OXYGEN SENSOR (LandCruiser RM000002W9N013X.html)

OK

4.CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT)

Disconnect the heated oxygen sensor connector.

Disconnect the ECM connector.

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

Standard Resistance:
for Automatic Transmission
Tester Connection
Condition
Specified Condition
C37-18 (HT1B) - C35-9 (OX1B)
Always
10 kΩ or higher
C37-13 (HT2B) - C35-3 (OX2B)
Always
10 kΩ or higher
for Manual Transmission
Tester Connection
Condition
Specified Condition
C37-12 (HT1B) - C34-2 (OX1B)
Always
10 kΩ or higher
C37-13 (HT2B) - C34-4 (OX2B)
Always
10 kΩ or higher

Reconnect the heated oxygen sensor connector.

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - HEATED OXYGEN SENSOR)

REPLACE ECM (LandCruiser RM00000329203TX.html)

5.PERFORM ACTIVE TEST USING GTS (INJECTION VOLUME)

Connect the GTS to the DLC3.

Start the engine.

Turn the GTS on.

Warm up the engine.

Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume.

Change the fuel injection volume using the GTS, and monitor the voltage output of the air fuel ratio sensor and heated oxygen sensor displayed on the GTS.

HINT:

Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine gradations within this range.
The air fuel ratio sensor is displayed as AFS Voltage B1S1 or AFS Voltage B2S1, and the heated oxygen sensor is displayed as O2S B1S2 or O2S B2S2 on the GTS.

Result
GTS Display (Sensor)	Voltage Variation	Proceed to
AFS Voltage B1S1 AFS Voltage B2S1 (Air fuel ratio sensor)	Alternates between higher than and below 3.3 V	OK
	Remains at higher than 3.3 V	NG
	Remains at below 3.3 V	NG

HINT:

A normal heated oxygen sensor voltage (O2S B1S2 or O2S B2S2) reacts in accordance with increases and decreases in fuel injection volumes. When the air fuel ratio sensor voltage remains at either below or higher than 3.3 V despite the heated oxygen sensor indicating a normal reaction, the air fuel ratio sensor is malfunctioning.

Go to step 15

OK

6.CHECK AIR FUEL RATIO SENSOR

HINT:

This air fuel ratio sensor test is to check the air fuel ratio sensor current during the fuel-cut operation. When the sensor is normal, the sensor current will be below 3 mA in this test.

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

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

Clear DTCs.

Drive the vehicle according to the driving pattern listed below:
1. Warm up the engine.
2. Drive the vehicle at 60 km/h (40 mph) or more for 10 minutes or more.
3. Stop the vehicle.
4. Accelerate the vehicle to 60 km/h (40 mph) or more and then decelerate for 5 seconds or more. Repeat this process at least 3 times.

Enter the following menus: Powertrain / Engine and ECT / Data List / AFS Current B1S1 and AFS Current B2S1.

Read the value of the air fuel ratio sensor current while the fuel-cut operation is being performed.
Standard current:
Below 3.0 mA
HINT:
1. To measure the air fuel ratio sensor current precisely, perform the fuel-cut operation as long as possible.
2. If it is difficult to measure the air fuel ratio sensor current, use the snapshot function of the GTS.

Result
Result	Proceed to
Outside standard range	A
Within standard range	B

Go to step 12

Go to step 15

7.PERFORM ACTIVE TEST USING GTS (INJECTION VOLUME)

Connect the GTS to the DLC3.

Start the engine.

Turn the GTS on.

Warm up the engine.

Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / All Data / O2S B1S2 or O2S B2S2.

Change the fuel injection volume using the GTS, monitoring the voltage output of the heated oxygen sensor displayed on the GTS.
HINT:
1. Change the fuel injection volume within the range of - 12% to +12%. The injection volume can be changed in fine gradations within this range.
2. The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.
Standard voltage:
Fluctuates between 0.4 V or less and 0.55 V or higher.

Go to step 9

OK

8.PERFORM ACTIVE TEST USING GTS (INJECTION VOLUME)

Connect the GTS to the DLC3.

Start the engine.

Turn the GTS on.

Warm up the engine.

Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume.

Change the fuel injection volume using the GTS, and monitor the voltage output of the air fuel ratio sensor and heated oxygen sensor displayed on the GTS.

HINT:

Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine gradations within this range.
The air fuel ratio sensor is displayed as AFS Voltage B1S1 or AFS Voltage B2S1, and the heated oxygen sensor is displayed as O2S B1S2 or O2S B2S2 on the GTS.

Result
GTS Display (Sensor)	Voltage Variation	Proceed to
AFS Voltage B1S1 AFS Voltage B2S1 (Air fuel ratio sensor)	Alternates between higher than and below 3.3 V	OK
	Remains at higher than 3.3 V	NG
	Remains at below 3.3 V	NG

HINT:

Go to step 15

CHECK EXTREMELY RICH OR LEAN ACTUAL AIR FUEL RATIO AND REPAIR CAUSE (FUEL INJECTOR, FUEL PRESSURE, GAS LEAK FROM SYSTEM, ETC.)

9.CHECK FOR EXHAUST GAS LEAK

Check for exhaust gas leakage.
OK:
No gas leak.
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after repairing or replacing the exhaust system (LandCruiser RM000004NJC03SX.html).

REPAIR OR REPLACE EXHAUST GAS LEAK POINT

OK

10.INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)

Inspect the heated oxygen sensor (LandCruiser RM000002RV6020X_01_0001.html).

REPLACE HEATED OXYGEN SENSOR (LandCruiser RM000002W9N013X.html)

OK

11.CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)

Disconnect the heated oxygen sensor connector.

Disconnect the ECM connector.

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

Standard Resistance (Check for Open):

for Automatic Transmission
Tester Connection	Condition	Specified Condition
C27-1 (HT1B) - C37-18 (HT1B)	Always	Below 1 Ω
C27-3 (OX1B) - C35-9 (OX1B)	Always	Below 1 Ω
C27-4 (E2) - C35-10 (EX1B)	Always	Below 1 Ω
C145-1 (HT2B) - C37-13 (HT2B)	Always	Below 1 Ω
C145-3 (OX2B) - C35-3 (OX2B)	Always	Below 1 Ω
C145-4 (E2) - C35-4 (EX2B)	Always	Below 1 Ω

for Manual Transmission
Tester Connection	Condition	Specified Condition
C27-1 (HT1B) - C37-12 (HT1B)	Always	Below 1 Ω
C27-3 (OX1B) - C34-2 (OX1B)	Always	Below 1 Ω
C27-4 (E2) - C34-1 (EX1B)	Always	Below 1 Ω
C28-1 (HT2B) - C37-13 (HT2B)	Always	Below 1 Ω
C28-3 (OX2B) - C34-4 (OX2B)	Always	Below 1 Ω
C28-4 (E2) - C34-3 (EX2B)	Always	Below 1 Ω

Standard Resistance (Check for Short):

for Automatic Transmission
Tester Connection	Condition	Specified Condition
C27-1 (HT1B) or C37-18 (HT1B) - Body ground	Always	10 kΩ or higher
C27-3 (OX1B) or C35-9 (OX1B) - Body ground	Always	10 kΩ or higher
C27-4 (E2) or C35-10 (EX1B) - Body ground	Always	10 kΩ or higher
C145-1 (HT2B) or C37-13 (HT2B) - Body ground	Always	10 kΩ or higher
C145-3 (OX2B) or C35-3 (OX2B) - Body ground	Always	10 kΩ or higher
C145-4 (E2) or C35-4 (EX2B) - Body ground	Always	10 kΩ or higher

for Manual Transmission
Tester Connection	Condition	Specified Condition
C27-1 (HT1B) or C37-12 (HT1B) - Body ground	Always	10 kΩ or higher
C27-3 (OX1B) or C34-2 (OX1B) - Body ground	Always	10 kΩ or higher
C27-4 (E2) or C34-1 (EX1B) - Body ground	Always	10 kΩ or higher
C28-1 (HT2B) or C37-13 (HT2B) - Body ground	Always	10 kΩ or higher
C28-3 (OX2B) or C34-4 (OX2B) - Body ground	Always	10 kΩ or higher
C28-4 (E2) or C34-3 (EX2B) - Body ground	Always	10 kΩ or higher

Reconnect the heated oxygen sensor connector.

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - HEATED OXYGEN SENSOR)

OK

12.REPLACE HEATED OXYGEN SENSOR

Replace the heated oxygen sensor (LandCruiser RM000002W9N013X.html).

NEXT

13.PERFORM CONFIRMATION DRIVING PATTERN

HINT:

Refer to Confirmation Driving Pattern.

NEXT

14.CHECK WHETHER DTC OUTPUT RECURS (DTC P0136, P0137, P0138, P0156, P0157 OR P0158)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

Input DTCs: P0136, P0137, P0138, P0156, P0157 and P0158.

Check that the DTC monitor is NORMAL. If the DTC monitor is INCOMPLETE, perform the driving pattern again by accelerating the vehicle and using the second gear to decelerate the vehicle.
Result
Result
Proceed to
NORMAL
(No DTC output)
A
ABNORMAL
(P0136, P0137, P0138, P0156, P0157 or P0158 stored)
B
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the air fuel ratio sensor (LandCruiser RM000004NJC03SX.html).

REPLACE AIR FUEL RATIO SENSOR (LandCruiser RM000002W9Q017X.html)

END

15.REPLACE AIR FUEL RATIO SENSOR

Replace the air fuel ratio sensor (LandCruiser RM000002W9Q017X.html).
HINT:
for Automatic Transmission
Perform "Inspection After Repair" after replacing the air fuel ratio sensor (LandCruiser RM000004NJC03SX.html).

NEXT

16.PERFORM CONFIRMATION DRIVING PATTERN

HINT:

Refer to Confirmation Driving Pattern.

NEXT

17.CHECK WHETHER DTC OUTPUT RECURS (DTC P0136, P0137, P0138, P0156, P0157 OR P0158)

Connect the GTS to the DLC3.

Turn the engine switch on (IG).

Turn the GTS on.

Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

Input DTCs: P0136, P0137, P0138, P0156, P0157 and P0158.

Check that the DTC monitor is NORMAL. If the DTC monitor is INCOMPLETE, perform the driving pattern again by accelerating the vehicle and using the second gear to decelerate the vehicle.
Result
Result
Proceed to
NORMAL
(No DTC output)
A
ABNORMAL
(P0136, P0137, P0138, P0156, P0157 or P0158 stored)
B

REPLACE HEATED OXYGEN SENSOR (LandCruiser RM000002W9N013X.html)

END

Result	Proceed to
P0138 or P0158	A
P0137 or P0157	B
P0136 or P0156	C

Result	Proceed to
NORMAL (No DTC output)	A
ABNORMAL (P0136, P0137, P0138, P0156, P0157 or P0158 stored)	B