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

In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx) components in the exhaust gas, a three-way catalytic converter is used. For the most efficient use of the three-way catalytic converter, the air fuel ratio must be precisely controlled so that it is always close to the stoichiometric air fuel level. 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. less than 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. more 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.

Corolla. Zre142 Aze141.2Zr-Fe Engine Control.Sfi System.
Dtc
P0136 Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 2)

DTC No.	DTC Detection Condition	Trouble Area
P0136	Either of the following conditions is met: Abnormal voltage output: During active air fuel ratio control, heated oxygen sensor voltage does not increase to 0.59 or more for certain period of time (2 trip detection logic) Low impedance: Sensor impedance less than 5 Ω for 30 seconds or more when ECM presumes sensor to being warmed up and operating normally (2 trip detection logic)	Heated oxygen sensor (sensor 2) circuit Heated oxygen sensor (sensor 2) Air fuel ratio sensor (sensor 1) Gas leak from exhaust system Fuel pressure Fuel injector assembly PCV valve and hose Intake system
P0137	Either of the following conditions is met: Low voltage (open): During active air fuel ratio control, following conditions (a) and (b) met for certain period of time (2 trip detection logic) (a) Heated oxygen sensor voltage output less than 0.21 V (b) Target air fuel ratio rich High impedance: Sensor impedance 15 kΩ or more for 90 seconds or more when ECM presumes sensor to be warmed up and operating normally (2 trip detection logic)	Heated oxygen sensor (sensor 2) circuit Heated oxygen sensor (sensor 2) Air fuel ratio sensor (sensor 1) Gas leak from exhaust system
P0138	Extremely high voltage (short): Heated oxygen sensor voltage output exceeds 1.2 V for 10 seconds or more (2 trip detection logic)	Heated oxygen sensor (sensor 2) circuit Heated oxygen sensor (sensor 2) ECM
P0139	Either of the following conditions is met (2 trip detection logic): Heated oxygen sensor (sensor 2) voltage does not drop to below 0.2 V immediately after fuel cut starts Heated oxygen sensor (voltage does not drop from 0.35 to 0.2 V immediately after air fuel cut starts)	Heated oxygen sensor (sensor 2) circuit Heated oxygen sensor (sensor 2) Gas leak from exhaust system

for Mexico Models
DTC No.	DTC Detection Conditions	Trouble Areas
P0136	Not applicable	None
P0137	Low voltage (open): During active air-fuel ratio control, both of the following conditions are met for a certain period of time (2 trip detection logic): (a) The Heated oxygen sensor voltage output is below 0.21 V. (b) The target air-fuel ratio is rich.	Heated oxygen sensor (sensor 2) circuit Heated oxygen sensor (sensor 2) Air fuel ratio sensor (sensor 1) Gas leak from exhaust system
P0138	Not applicable	None
P0139	Not applicable	None

MONITOR DESCRIPTION

Active Air Fuel Ratio Control

The ECM usually performs air fuel ratio feedback control so that the air fuel ratio sensor output indicates a near stoichiometric air fuel level. This vehicle includes active air fuel ratio control in addition to regular air fuel ratio control. The ECM performs active air fuel ratio control to detect any deterioration in the three-way catalytic converter and heated oxygen sensor malfunctions (refer to the diagram below).
Active air fuel ratio control is performed for approximately 15 to 20 seconds while driving with a warm engine. During active air fuel ratio control, the air fuel ratio is forcibly regulated to become lean or rich by the ECM. If the ECM detects a malfunction, a DTC is set.

Abnormal Voltage Output of Heated Oxygen Sensor (DTC P0136)

While the ECM is performing active air fuel ratio control, the air fuel ratio is forcibly regulated to become rich or lean. If the sensor is not functioning properly, the voltage output variation is small. For example, when the heated oxygen sensor voltage does not increase to 0.59 V or more during active air fuel ratio control, the ECM determines that the sensor voltage output is abnormal and sets DTCs P0136.

Open or Short in Heated Oxygen Sensor Circuit (DTC P0137)

During active air fuel ratio control, the ECM calculates the oxygen storage capacity* of the three-way catalytic converter by forcibly regulating the air fuel ratio to become rich or lean.
If the heated oxygen sensor has an open circuit, or the voltage output of the sensor noticeably decreases, the oxygen storage capacity indicates an extraordinarily high value. Even if the ECM attempts to continue regulating the air fuel ratio to become rich or lean, the heated oxygen sensor output does not change.
While performing active air fuel ratio control, when the target air fuel ratio is rich and the heated oxygen sensor voltage output is less than 0.21 V (lean), the ECM interprets this as an abnormally low sensor output voltage and sets DTC P0137.

HINT:

*: The three-way catalytic converter has the capability to store oxygen. The oxygen storage capacity and the emission purification capacity of the three-way catalytic converter are mutually related. The ECM determines whether the catalyst has deteriorated, based on the calculated oxygen storage capacity value (COROLLA_ZRE142 RM000000WC00E0X.html).

High or Low Impedance of Heated Oxygen (HO2) Sensor (DTC P0136 or P0137)

During normal air fuel ratio feedback control, there are small variations in the exhaust gas oxygen concentration. In order to continuously monitor the slight variation of the heated oxygen sensor signal while the engine is running, the impedance* of the sensor is measured by the ECM. The ECM determines that there is a malfunction in the sensor when the measured impedance deviates from the standard range.
*: The effective resistance in an alternating current electrical circuit.

HINT:

The impedance cannot be measured using an ohmmeter.
DTC P0136 indicates the deterioration of the heated oxygen sensor. The ECM sets the DTCs by calculating the impedance of the sensor when the typical enabling conditions are satisfied (2 driving cycles).
DTC P0137 indicates an open or short circuit in the heated oxygen sensor (2 driving cycles). The ECM sets the DTCs when the impedance of the sensor exceeds the threshold of 15 kΩ.

Extremely High Output Voltage of Heated Oxygen Sensor (DTC P0138)

The ECM continuously monitors the heated oxygen sensor output voltage while the engine is running. DTC P0138 is stored if the heated oxygen sensor voltage output is 1.2 V or more for 10 seconds or more.

Abnormal Voltage Output of Heated Oxygen Sensor During Fuel-cut (DTC P0139)

The sensor output voltage drops to below 0.2 V (extremely Lean status) immediately when the vehicle decelerates and fuel cut is operating. If the voltage does not drop to below 0.2 V for 7 seconds or more, or the voltage does not drop from 0.35 to 0.2 V for 1 second, the ECM determines that the sensor response has deteriorated, illuminates the MIL and sets a DTC.

MONITOR STRATEGY

Related DTCs	P0136: Heated oxygen sensor (bank 1) voltage check (voltage malfunction) P0136: Heated oxygen sensor (bank 1) circuit continuity check (circuit short) P0137: Heated oxygen sensor (bank 1) voltage check (low voltage) P0136: Heated oxygen sensor (bank 1) circuit continuity check (circuit open) P0138: Heated oxygen sensor (bank 1) circuit continuity check (out of range) P0139: Heated oxygen sensor (bank 1) response rate during fuel cut
Required Sensors/Components (Main)	Heated oxygen sensor (sensor 2)
Required Sensors/Components (Related)	Crankshaft position sensor Engine coolant temperature sensor Mass air flow meter sub-assembly Throttle position sensor Air fuel ratio sensor
Frequency of Operation	Once per driving cycle: Active air fuel ratio control detection, heated oxygen sensor abnormal voltage during fuel cut. Continuous: Other
Duration	20 seconds: Heated oxygen sensor voltage check 30 seconds: Heated oxygen sensor circuit continuity check (circuit short) 90 seconds: Heated oxygen sensor circuit continuity check (circuit open) 10 seconds: Heated oxygen sensor circuit continuity check (out of range) 7 seconds: Heated oxygen sensor response rate during fuel cut
MIL Operation	2 driving cycles
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

All
Monitor runs whenever following DTCs not present	P0016 (VVT System - Misalignment) P0017 (Exhaust VVT System - Misalignment) P0031, P0032 (Air Fuel Ratio Sensor Heater - Sensor 1) P0037, P0038 (Heated Oxygen Sensor Heater - Sensor 2) P0102, P0103 (Mass Air Flow Meter) P0112, P0113 (Intake Air Temperature Sensor) P0115, P0117, P0118 (Engine Coolant Temperature Sensor) P0120, P0121 P0122, P0123, P0220, P0222, P0223, P2135 (Throttle Position Sensor) P0125 (Insufficient Engine Coolant Temperature for Closed Loop Fuel Control) P0128 (Thermostat) P0171, P0172 (Fuel System) P0301, P0302, P0303, P0304 (Misfire) P0335 (Crankshaft Position Sensor) P0340, P0342, P0343 (Camshaft Position Sensor) P0451, P0452, P0453 (EVAP System) P0500 (Vehicle Speed Sensor) P2195, P2196, P2237, P2238, P2239, P2252, P2253, P2A00 (Air Fuel Ratio Sensor - Sensor 1) P219A (Air Fuel Ratio Imbalance)

P0136 and P0137: Heated Oxygen Sensor Voltage Check (Voltage Malfunction and Low Voltage)
Battery voltage	11 V or more
Intake air temperature	-10°C (14°F) or more
Engine coolant temperature	75°C (167°F) or more
Atmospheric pressure	76 kPa(abs) [570 mmHg(abs)] or higher
Idling	Off
Engine speed	Less than 4000 rpm
Air fuel ratio sensor status	Activated
Fuel system status	Closed loop
Engine load	10% or more, and less than 80%
Shift position	4th or more

P0136: Heated Oxygen Sensor Circuit Continuity Check (Circuit Short)
Battery voltage	11 V or more
Estimated heated oxygen sensor temperature	Less than 700°C (1292°F)
ECM monitor	Completed
DTC P0607	Not set

P0137: Heated Oxygen Sensor Circuit Continuity Check (Circuit Open)
Battery voltage	11 V or higher
Estimated heated oxygen sensor temperature	450°C (842°F) or more, and less than 750°C (1382°F)
DTC P0607	Not set

P0138: Heated Oxygen Sensor Circuit Continuity Check (Out of Range)
Battery voltage	11 V or higher
Time after engine start	2 seconds or more

P0139: Heated Oxygen Sensor Response Rate During Fuel Cut
Engine coolant temperature	75°C (167°F) or more
Catalyst temperature	400°C (752°F) or more
Fuel cut	On

TYPICAL MALFUNCTION THRESHOLDS

P0136: Heated Oxygen Sensor Voltage Check (Voltage Malfunction)
All of the following conditions (a), (b) and (c) met	-
(a) OSC (Oxygen Storage Capacity) of catalyst	2 g or more
(b) Commanded air fuel ratio	14.2 or less
(c) Heated oxygen sensor voltage	0.21 V or more, and less than 0.59 V

P0137: Heated Oxygen Sensor Voltage Check (Low Voltage)
All of the following conditions (a), (b) and (c) met	-
(a) OSC (Oxygen Storage Capacity) of catalyst	2 g or more
(b) Commanded air fuel ratio	14.2 or less
(c) Heated oxygen sensor voltage	Less than 0.21 V

P0136: Heated Oxygen Sensor Circuit Continuity Check (Circuit Short)
Duration of following condition	30 seconds or more
Heated oxygen sensor impedance	Less than 5 Ω

P0137: Heated Oxygen Sensor Circuit Continuity Check (Circuit Open)
Duration of following condition	90 seconds or more
Heated oxygen sensor impedance	15 kΩ or more

P0138: Heated Oxygen Sensor Circuit Continuity Check (Out of Range)
Duration of following condition	10 seconds or more
Heated oxygen sensor voltage	1.2 V or more

P0139: Heated Oxygen Sensor Response Rate During Fuel Cut
Either of the following conditions is met	-
Duration until heated oxygen sensor voltage drops to 0.2 V after fuel cut	7 seconds or more
Duration until heated oxygen sensor voltage drops from 0.35 V to 0.2 V during fuel cut	1 second or more

MONITOR RESULT

Refer to Checking Monitor Status (Link).

CONFIRMATION DRIVING PATTERN

HINT:

This confirmation driving pattern is used in the "Perform Confirmation Driving Pattern" procedure of the following diagnostic troubleshooting procedure.
Performing this confirmation driving pattern will activate the heated oxygen sensor monitor (The catalyst monitor is performed simultaneously). This is very useful for verifying the completion of a repair.

P0136, P0137 and P0138

Connect the Techstream to the DLC3.
Turn the ignition switch to ON and turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation) (COROLLA_ZRE142 RM000000PDK0ZAX.html).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON and turn the Techstream on [A].
Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher [B].
With the transaxle in D or 4th gear or more, drive the vehicle at 37 and 75 mph (60 and 120 km/h) for 10 minutes or more [C].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [D].
Read the pending DTCs.
HINT:
1. If a pending DTC is output, the system is malfunctioning.
2. If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P0136, P0137 or P0138.

Check the DTC judgment result.

Techstream 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

HINT:

If the judgment result shows NORMAL, the system is normal.
If the judgment result shows ABNORMAL, the system has a malfunction.
If the judgment result shows INCOMPLETE or N/A, perform steps [C] and [D] again.

If no pending DTC is output, perform a universal trip and check for permanent DTCs (COROLLA_ZRE142 RM000000PDK0ZAX.html).
HINT:
1. If a permanent DTC is output, the system is malfunctioning.
2. If no permanent DTC is output, the system is normal.

P0139

Connect the Techstream to the DLC3.
Turn the ignition switch to ON and turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation) (COROLLA_ZRE142 RM000000PDK0ZAX.html).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON and turn the Techstream on [A].
Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher [B].
Drive the vehicle at 37 mph (60 km/h), and then decelerate the vehicle by releasing the accelerator pedal for 5 seconds or more to perform the fuel-cut [C].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [D].
Read the pending DTCs.
HINT:
1. If a pending DTC or current DTC is output, the system is malfunctioning.
2. If a pending DTC or current DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P0139.

Check the DTC judgment result.

Techstream 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

HINT:

If the judgment result shows NORMAL, the system is normal.
If the judgment result shows ABNORMAL, the system has a malfunction.
If the judgment result shows INCOMPLETE or N/A, shift the transaxle to 2nd gear, and then perform steps [C] and [D] again.

If no pending DTC is output, perform a universal trip and check for permanent DTCs (COROLLA_ZRE142 RM000000PDK0ZAX.html).
HINT:
1. If a permanent DTC is output, the system is malfunctioning.
2. If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

Malfunctioning areas can be identified by performing the Control the Injection Volume function provided in the Active Test. The Control the Injection Volume 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 operation using the Techstream.

Connect the Techstream to the DLC3.
Start the engine.
Turn the Techstream 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 / Gas AF Control / AFS Voltage B1S1 and O2S B1S2.
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 and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2) displayed on the Techstream.

HINT:

Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine gradations.
Each sensor reacts in accordance with increases and decreases in the fuel injection volume.

Techstream Display (Sensor)	Injection Volume	Status	Voltage
AFS Voltage B1S1 (Air fuel ratio)	+12%	Rich	Below 3.1 V
AFS Voltage B1S1 (Air fuel ratio)	-12%	Lean	Higher than 3.4 V
O2S B1S2 (Heated oxygen)	+12%	Rich	Higher than 0.55 V
O2S B1S2 (Heated oxygen)	-12%	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 leak from exhaust system (Air fuel ratio extremely rich or lean)

Following the Control the Injection Volume procedure enables technicians to check and graph the voltage outputs of both the air fuel ratio and heated oxygen sensors.
To display the graph, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / Gas AF Control / AFS Voltage B1S1 and O2S B1S2; and then press the graph button on the Data List view.

HINT:

Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
Sensor 1 refers to the sensor closest to the engine assembly.
Sensor 2 refers to the sensor farthest away from the engine assembly.

1.READ DTC OUTPUT (DTC P0136, P0137, P0138 OR P0139)

Connect the Techstream to the DLC3.

Turn the ignition switch to ON.

Turn the Techstream on.

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

Read DTCs.

Result:

Result
Proceed to
DTC P0138 is output
A
DTC P0137 is output
B
DTC P0136 is output
C
DTC P0139 is output
D
DTC P0136, P0137 or P0138 and other DTCs are output
E
HINT:
If any DTCs other than P0136, P0137, P0138 or P0139 are output, troubleshoot those DTCs first.

Go to step 6

Go to step 4

Go to step 15

GO TO DTC CHART (COROLLA_ZRE142 RM000000PDF0G8X.html)

A

2.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:
Tester Connection
Condition
Specified Condition
1 (+B) - 3 (E2)
Always
10 kΩ or higher
1 (+B) - 4 (OX1B)

Reconnect the heated oxygen sensor connector.

REPLACE HEATED OXYGEN SENSOR (COROLLA_ZRE142 RM00000306V015X.html)

OK

3.CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT)

Turn the ignition switch off and wait for 5 minutes or more.

Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection
Condition
Specified Condition
B31-63 (HT1B) - B31-80 (OX1B)
Always
10 kΩ or higher

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR

REPLACE ECM (COROLLA_ZRE142 RM000001CN0030X.html)

4.PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME)

Connect the Techstream to the DLC3.

Start the engine.

Turn the Techstream on.

Warm up the engine.

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

Change the fuel injection volume using the Techstream, monitoring the voltage output of the heated oxygen sensors displayed on the Techstream.
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 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 6

OK

5.PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME)

Connect the Techstream to the DLC3.

Turn the ignition switch to ON.

Turn the Techstream on.

Start the engine and warm it up.

Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / All Data / AFS Voltage B1S1 or O2S B1S2.

Change the fuel injection volume using the Techstream, and monitor the voltage output of air fuel ratio and heated oxygen sensors displayed on the Techstream.
HINT:
1. Change the fuel injection volume within the range of -12% and +12%. The injection volume can be changed in fine graduations within this range.
2. The air fuel ratio sensor is displayed as AFS Voltage B1S1, and the heated oxygen sensor is displayed as O2S B1S2 on the Techstream.
3. 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.
4. If there is almost no response from the air fuel ratio sensor, a malfunction of the air fuel ratio sensor is suspected.
Result:

Techstream Display (Sensor)
Voltage Variation
Proceed to
AFS Voltage B1S1
(Air fuel ratio)
Alternates between more and less than 3.3 V
OK
Remains at more than 3.3 V
NG
Remains at less than 3.3 V
NG
HINT:
A normal heated oxygen sensor voltage (O2S B1S2) reacts in accordance with increases and decreases in fuel injection volumes. When the air fuel ratio sensor voltage remains at either less or more than 3.3 V despite the heated oxygen sensor indicating a normal reaction, the air fuel ratio sensor is malfunctioning.

Go to step 12

CHECK ENGINE TO DETERMINE CAUSE OF EXTREMELY RICH OR LEAN ACTUAL AIR FUEL RATIO (FUEL INJECTOR ASSEMBLY, FUEL SYSTEM, INTAKE SYSTEM, ETC.) (COROLLA_ZRE142 RM000000WC30N3X.html)

6.CHECK FOR EXHAUST GAS LEAK

Check for exhaust gas leaks.
OK:
No gas leaks.

REPAIR OR REPLACE EXHAUST GAS LEAK POINT

OK

7.INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)

Inspect the heated oxygen sensor (COROLLA_ZRE142 RM000001CK804AX.html).

REPLACE HEATED OXYGEN SENSOR (COROLLA_ZRE142 RM00000306V015X.html)

OK

8.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):

Tester Connection
Condition
Specified Condition
E86-2 (HT1B) - B31-63 (HT1B)
Always
Below 1 Ω
E86-4 (OX1B) - B31-80 (OX1B)
Always
Below 1 Ω
E86-3 (E2) - B31-79 (O1B-)
Always
Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection
Condition
Specified Condition
E86-2 (HT1B) or B31-63 (HT1B) - Body ground
Always
10 kΩ or higher
E86-4 (OX1B) or B31-80 (OX1B) - Body ground
Always
10 kΩ or higher

Reconnect the heated oxygen sensor connector.

Reconnect the ECM connector.

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

OK

9.REPLACE HEATED OXYGEN SENSOR

Replace the heated oxygen sensor (COROLLA_ZRE142 RM00000306V015X.html).

NEXT

10.PERFORM CONFIRMATION DRIVING PATTERN

Refer to the Confirmation Driving Pattern for P0136, P0137 and P0138.

NEXT

11.CHECK WHETHER DTC OUTPUT RECURS (P0136 OR P0137)

Connect the Techstream to the DLC3.

Turn the ignition switch to ON.

Turn the Techstream on.

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

Input DTCs: P0136 or P0137.

Check that the DTC monitor is NORMAL. If the DTC monitor is INCOMPLETE, perform the driving pattern again but increase the vehicle speed.

Result:

Result
Proceed to
ABNORMAL
(DTC P0136 or P0137 is output)
A
NORMAL
(DTC is not output)
B

END

REPLACE AIR FUEL RATIO SENSOR (COROLLA_ZRE142 RM00000306S01AX.html)

12.REPLACE AIR FUEL RATIO SENSOR

Replace the air fuel ratio sensor (COROLLA_ZRE142 RM00000306S01AX.html).

NEXT

13.PERFORM CONFIRMATION DRIVING PATTERN

Refer to the Confirmation Driving Pattern for P0136, P0137 and P0138.

NEXT

14.CHECK WHETHER DTC OUTPUT RECURS (P0136)

Connect the Techstream to the DLC3.

Turn the ignition switch to ON.

Turn the Techstream on.

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

Input DTC: P0136.

Check that the DTC monitor is NORMAL. If the DTC monitor is INCOMPLETE, perform the driving pattern again but increase the vehicle speed.

Result:

Result
Proceed to
ABNORMAL
(DTC P0136 is output)
A
NORMAL
(DTC is not output)
B

END

REPLACE HEATED OXYGEN SENSOR (COROLLA_ZRE142 RM00000306V015X.html)

15.CHECK FOR EXHAUST GAS LEAK

Check for exhaust gas leaks.
OK:
No gas leaks.

REPAIR OR REPLACE EXHAUST GAS LEAK POINT

OK

16.CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT)

Turn the ignition switch off and wait for 5 minutes or more.

Disconnect the ECM connector.

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

Standard Resistance:

Tester Connection
Condition
Specified Condition
B31-63 (HT1B) - B31-80 (OX1B)
Always
10 kΩ or higher

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

17.PERFORM CONFIRMATION DRIVING PATTERN

Perform Confirmation Driving Pattern for P0139.

NEXT

18.READ DTC OUTPUT (CHECK WHETHER DTC P0139 IS OUTPUT AGAIN)

Connect the Techstream to the DLC3.

Turn the ignition switch to ON.

Turn the Techstream on.

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

Input DTC: P0139.

Check that the DTC monitor is NORMAL. If the DTC monitor is INCOMPLETE, perform the driving pattern again but increase the vehicle speed.

Result:

Result
Proceed to
ABNORMAL (DTC P0139 is output)
A
NORMAL (DTC is not output)
B

CHECK FOR INTERMITTENT PROBLEMS (COROLLA_ZRE142 RM000000PDQ0VMX.html)

REPLACE HEATED OXYGEN SENSOR (COROLLA_ZRE142 RM00000306V015X.html)

Result	Proceed to
DTC P0138 is output	A
DTC P0137 is output	B
DTC P0136 is output	C
DTC P0139 is output	D
DTC P0136, P0137 or P0138 and other DTCs are output	E

Tester Connection	Condition	Specified Condition
1 (+B) - 3 (E2)	Always	10 kΩ or higher
1 (+B) - 4 (OX1B)	Always	10 kΩ or higher

Techstream Display (Sensor)	Voltage Variation	Proceed to
AFS Voltage B1S1 (Air fuel ratio)	Alternates between more and less than 3.3 V	OK
	Remains at more than 3.3 V	NG
	Remains at less than 3.3 V	NG

Result	Proceed to
ABNORMAL (DTC P0136 or P0137 is output)	A
NORMAL (DTC is not output)	B

Result	Proceed to
ABNORMAL (DTC P0136 is output)	A
NORMAL (DTC is not output)	B

Result	Proceed to
ABNORMAL (DTC P0139 is output)	A
NORMAL (DTC is not output)	B