DTC    P0136    Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 2)

DTC    P0137    Oxygen Sensor Circuit Low Voltage (Bank 1 Sensor 2)

DTC    P0138    Oxygen Sensor Circuit High Voltage (Bank 1 Sensor 2)

DTC    P0139    Oxygen Sensor Circuit Slow Response (Bank 1 Sensor 2)

for Preparation Click here


DESCRIPTION

A three-way catalytic converter (TWC) is used in order to convert the carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NOx) 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, the 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 great. 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 small. The heated oxygen sensor informs the ECM that the post-TWC 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.

A210509E03


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

for Mexico Models 
DTC No.
DTC Detection Conditions
Trouble Areas
P0136
Not applicable
None
P0137
  1. Low voltage (open):
    1. During active air-fuel ratio control, both of the following conditions are met for a certain period of time (2 trip detection logic):
      1. (a) The Heated oxygen sensor voltage output is below 0.21 V.
      2. (b) The target air-fuel ratio is rich.
  1. Heated oxygen sensor (sensor 2) circuit
  2. Heated oxygen sensor (sensor 2)
  3. Air fuel ratio sensor (sensor 1)
  4. 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 (A/F) 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 (TWC) and Heated Oxygen (HO2) 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 stored.

Abnormal Voltage Output of Heated Oxygen (HO2) 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 higher during active air fuel ratio control, the ECM determines that the sensor voltage output is abnormal and stores DTCs P0136.

A152942E44


Open in Heated Oxygen (HO2) Sensor Circuit (DTC P0137)
During active air fuel ratio control, the ECM calculates the Oxygen Storage Capacity (OSC)* of the Three-Way Catalytic Converter (TWC) 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 OSC 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 stores DTC P0137.

HINT:
*: The TWC has the capability to store oxygen. The OSC and the emission purification capacity of the TWC are mutually related. The ECM determines whether the catalyst has deteriorated, based on the calculated OSC value (Click here).

A234468E19


High or Low Impedance of Heated Oxygen (HO2) Sensor (DTCs 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.
A076841E32

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

Extremely High Output Voltage of Heated Oxygen (HO2) 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 higher for 10 seconds or more.

Abnormal Voltage Output of Heated Oxygen (HO2) 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 voltage does not drop from 0.35 V to 0.2 V for 1 second or more, the ECM determines that the sensor response has deteriorated, illuminates the MIL and stores a DTC.

MONITOR STRATEGY


Related DTCs
P0136: Heated oxygen sensor output voltage (Output voltage)
P0136: Heated oxygen sensor impedance (Low)
P0137: Heated oxygen sensor output voltage (Low voltage)
P0137: Heated oxygen sensor impedance (High)
P0138: Heated oxygen sensor output voltage (Extremely high)
P0139: Heated oxygen sensor output voltage 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
Throttle position sensor
Frequency of Operation
Once per driving cycle: Active air fuel ratio control detection, Heated oxygen sensor output voltage during fuel cut
Continuous: Other
Duration
7 seconds: Heated oxygen sensor voltage during fuel cut
10 seconds: Heated oxygen sensor voltage (Extremely high)
20 seconds: Heated oxygen sensor output (Output voltage, Low voltage)
30 seconds: Heated oxygen sensor impedance (Low)
90 seconds: Heated oxygen sensor impedance (High)
MIL Operation
2 driving cycles
Sequence of Operation
None

TYPICAL ENABLING CONDITIONS


All: 
Monitor runs whenever following DTCs are not present
P0016 (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)
P014C, P014D, P015A, P015B, P2195, P2196, P2237, P2238, P2239, P2252, P2253 (Air Fuel Ratio Sensor - Sensor 1)
P0171, P0172 (Fuel System)
P0301, P0302, P0303, P0304 (Misfire)
P0335 (Crankshaft Position Sensor)
P0340 (Camshaft Position Sensor)
P0451, P0452, P0453 (EVAP System)
P0500 (Vehicle Speed Sensor)

Heated Oxygen Sensor Output Voltage (Output Voltage and Low Voltage): 
Catalyst monitor precondition
Met
Catalyst monitor precondition defined as when all of the following conditions met:
-
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 (570 mmHg) or more
Idle
Off
Engine speed
Less than 4000 rpm
Air fuel ratio sensor
Activated
Fuel system status
Closed loop
Engine load
10 to 80%

Heated Oxygen Sensor Impedance (Low): 
Battery voltage
11 V or more
Estimated sensor temperature
Less than 700°C (1292°F)
ECM monitor
Completed
DTC P0607
Not set

Heated Oxygen Sensor Impedance (High): 
Battery voltage
11 V or more
Estimated sensor temperature
450°C (842°F) or more, less than 750°C (1382°F)
DTC P0607
Not set

Heated Oxygen Sensor Output Voltage (Extremely High): 
Battery voltage
11 V or more
Time after engine start
2 seconds or more

Heated Oxygen Sensor Voltage During Fuel Cut: 
Engine coolant temperature
75°C (167°F) or more
Estimated catalyst temperature
400°C (752°F) or more
Fuel cut
On

TYPICAL MALFUNCTION THRESHOLDS


Heated Oxygen Sensor Output Voltage (Output voltage): 
All of following conditions (a), (b) and (c) are met
-
(a) Commanded air fuel ratio
14.3 or less
(b) Heated oxygen sensor voltage
0.21 to 0.59 V
(c) Oxygen storage capacity of catalyst
2.0 g or more

Heated Oxygen Sensor Output Voltage (Low output voltage): 
All of following conditions (a), (b) and (c) are met
-
(a) Commanded air fuel ratio
14.3 or less
(b) Heated oxygen sensor voltage
Less than 0.21 V
(c) Oxygen storage capacity of catalyst
2.0 g or more

Heated Oxygen Sensor Impedance (Low): 
Duration of following condition
30 seconds or more
Heated oxygen sensor impedance
Less than 5 Ω

Heated Oxygen Sensor Impedance (High): 
Duration of following condition
90 seconds or more
Heated oxygen sensor impedance
15 kΩ or more

Heated Oxygen Sensor Output Voltage (Extremely High): 
Duration of following condition
10 seconds or more
Heated oxygen sensor voltage
1.2 V or more

Heated Oxygen Sensor Voltage During Fuel Cut: 
Duration until heated oxygen sensor voltage drops to 0.2 V after fuel cut
7 seconds or more
Duration that 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 (Click here).

CONFIRMATION DRIVING PATTERN

HINT:
  1. This confirmation driving pattern is used in the "Perform Confirmation Driving Pattern" procedure of the following diagnostic troubleshooting procedure.
  2. Performing this confirmation driving pattern will activate the Heated Oxygen (HO2) sensor monitor (The catalyst monitor is performed simultaneously). This is very useful for verifying the completion of a repair.
  1. P0136, P0137 and P0138

A264212E04

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off and wait for at least 30 seconds.
  5. Turn the ignition switch to ON and turn the Techstream on [A].
  6. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher [B].
  7. Drive the vehicle at 60 to 120 km/h (37 to 75 mph) for 10 minutes or more [C].

    CAUTION:
    When performing the confirmation driving pattern, obey all speed limits and traffic laws.
  8. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [D].
  9. 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.
  10. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  11. Input the DTC: P0136, P0137 or P0138.
  12. Check the DTC judgment result.

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

    HINT:
    1. If the judgment result shows NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
    3. If the judgment result shows INCOMPLETE or N/A, perform steps [C] and [D] again.
  13. If no pending DTC is output, perform a universal trip and check for permanent DTCs (Click here).

    HINT:
    1. If a permanent DTC is output, the system is malfunctioning.
    2. If no permanent DTC is output, the system is normal.
  1. P0139

A199377E76

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off and wait for at least 30 seconds.
  5. Turn the ignition switch to ON and turn the Techstream on [A].
  6. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher [B].
  7. Drive the vehicle at 60 km/h (37 mph), 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.
  8. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [D].
  9. Read the 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.
  10. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  11. Input the DTC: P0139.
  12. Check the DTC judgment result.

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

    HINT:
    1. If the judgment result shows NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
    3. If the judgment result shows INCOMPLETE or N/A, move the shift lever to 2nd and then perform steps [C] and [D] again.
  13. If no pending DTC is output, perform a universal trip and check for permanent DTCs (Click here).

    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


A182697E04


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.
  1. Connect the Techstream to the DLC3.
  2. Start the engine.
  3. Turn the Techstream on.
  4. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.
  5. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / Gas AF Control / AFS Voltage B1S1 and O2S B1S2.
  6. Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).
  7. Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2) 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.
  2. 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
-12%
Lean
Higher than 3.4 V
O2S B1S2
(Heated oxygen)
+12%
Rich
Higher than 0.55 V
-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
A150787E05
A151324E08
A150787E05
A150788E06
-
2
A150787E05
A150790E01
A150787E05
A150788E06
  1. Air fuel ratio sensor
  2. Air fuel ratio sensor heater
  3. Air fuel ratio sensor circuit
3
A150787E05
A151324E08
A150787E05
A150790E01
  1. Heated oxygen sensor
  2. Heated oxygen sensor heater
  3. Heated oxygen sensor circuit
4
A150787E05
A150790E01
A150787E05
A150790E01
  1. Fuel injector assembly
  2. Fuel pressure
  3. Gas leak from exhaust system (Air fuel ratio extremely rich or lean)
  1. 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.
  2. 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.

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:
  1. Sensor 1 refers to the sensor closest to the engine assembly.
  2. Sensor 2 refers to the sensor farthest away from the engine assembly.
  3. Read freeze frame data using the Techstream. 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 OR P0139)
  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

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

  1. Read DTCs.

    Result:

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


B
Go to step 6

C
Go to step 4

D
Go to step 15

E
GO TO DTC CHART (Click here)
A


2.INSPECT HEATED OXYGEN SENSOR (CHECK FOR SHORT)
A170692E05
  1. Disconnect the heated oxygen sensor connector.

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    2 (+B) - 4 (E2)
    Always
    10 kΩ or higher
    2 (+B) - 3 (OX1B)
  1. Reconnect the heated oxygen sensor connector.



NG
REPLACE HEATED OXYGEN SENSOR (Click here)
OK


3.CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT)
  1. Turn the ignition switch off and wait for 5 minutes or more.

  1. Disconnect the ECM connector.

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

    Standard Resistance:

    Tester Connection
    Condition
    Specified Condition
    B31-47 (HT1B) - B31-64 (OX1B)
    Always
    10 kΩ or higher
  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ECM (Click here)  

4.PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE INJECTION VOLUME)
  1. Connect the Techstream to the DLC3.

  1. Start the engine.

  1. Turn the Techstream on.

  1. Warm up the engine.

  1. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / Gas AF Control / O2S B1S1.

  1. 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 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.


NG
Go to step 6
OK


5.PERFORM ACTIVE TEST USING TECHSTREAM (INJECTION VOLUME)
  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Warm up the engine.

  1. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / Gas AF Control / AFS Voltage B1S1 and O2S B1S2.



  1. 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% to +12%. The injection volume can be changed in fine gradations 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 the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.

    Result 
    Techstream Display (Sensor)
    Voltage Variation
    Proceed to
    AFS Voltage B1S1 (Air fuel ratio)
    Alternates between higher and less than 3.3 V
    OK
    Remains at higher 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 (AFS Voltage B1S1) remains at either less or higher than 3.3 V despite the heated oxygen sensor indicating a normal reaction, the air fuel ratio sensor is malfunctioning.

    A121606E22



NG
Go to step 12
OK

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

6.CHECK FOR EXHAUST GAS LEAK
  1. Check for exhaust gas leaks.

OK:
No gas leaks.


NG
REPAIR OR REPLACE EXHAUST GAS LEAK POINT
OK


7.INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)
  1. Inspect the heated oxygen sensor (Click here).



NG
REPLACE HEATED OXYGEN SENSOR (Click here)
OK


8.CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)
  1. Disconnect the heated oxygen sensor connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    Tester Connection
    Condition
    Specified Condition
    B24-1 (HT1B) - B31-47 (HT1B)
    Always
    Below 1 Ω
    B24-3 (OX1B) - B31-64 (OX1B)
    B24-4 (E2) - B31-87 (EX1B)

    Standard Resistance (Check for Short):

    Tester Connection
    Condition
    Specified Condition
    B24-1 (HT1B) or B31-47 (HT1B) - Body ground
    Always
    10 kΩ or higher
    B24-3 (OX1B) or B31-64 (OX1B) - Body ground
  1. Reconnect the heated oxygen sensor connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


9.REPLACE HEATED OXYGEN SENSOR
  1. Replace the heated oxygen sensor (Click here).


NEXT


10.PERFORM CONFIRMATION DRIVING PATTERN
  1. Perform the Confirmation Driving Pattern (P0136, P0137 and P0138).


NEXT


11.CHECK WHETHER DTC OUTPUT RECURS (DTC P0136 OR P0137)
  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

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

  1. Input DTCs: P0136 or P0137.

  1. 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
    (P0136 and P0137)
    A
    NORMAL
    (No output)
    B


B
END
A

REPLACE AIR FUEL RATIO SENSOR (Click here)  

12.REPLACE AIR FUEL RATIO SENSOR
  1. Replace the air fuel ratio sensor (Click here).


NEXT


13.PERFORM CONFIRMATION DRIVING PATTERN
  1. Perform Confirmation Driving Pattern (P0136, P0137 and P0138).


NEXT


14.CHECK WHETHER DTC OUTPUT RECURS (DTC P0136)
  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

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

  1. Input DTCs: P0136.

  1. 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
    (P0136)
    A
    NORMAL
    (No output)
    B


B
END
A

REPLACE HEATED OXYGEN SENSOR (Click here)  

15.CHECK FOR EXHAUST GAS LEAK
  1. Check for exhaust gas leaks.

OK:
No gas leaks.


NG
REPAIR OR REPLACE EXHAUST GAS LEAK POINT
OK


16.CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT)
  1. Turn the ignition switch off and wait for 5 minutes.

  1. Disconnect the ECM connector.

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


Standard Resistance:

Tester Connection
Condition
Specified Condition
B31-47 (HT1B) - B31-64 (OX1B)
Always
10 kΩ or higher
  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


17.PERFORM CONFIRMATION DRIVING PATTERN
  1. Perform Confirmation Driving Pattern (P0139).


NEXT


18.READ DTC OUTPUT (CHECK WHETHER DTC P0139 IS OUTPUT AGAIN)
  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

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

  1. Read DTC.


Result:

Result
Proceed to
P0139
A
No output
B


B
CHECK FOR INTERMITTENT PROBLEMS (Click here)
A

REPLACE HEATED OXYGEN SENSOR (Click here)