SFI SYSTEM (w/ EGR System), Diagnostic DTC:P0136, P0137, P0138

DTC Code DTC Name
P0136 Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 2)
P0137 Oxygen Sensor Circuit Low Voltage (Bank 1 Sensor 2)
P0138 Oxygen Sensor Circuit High Voltage (Bank 1 Sensor 2)

DESCRIPTION

Tech Tips

Sensor 2 refers to the sensor mounted behind the Three-Way Catalytic Converter (TWC) and located far from the engine assembly.

In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbons (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. 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.

A003VC2E05
DTC No. DTC Detection Condition Trouble Area
P0136*

Abnormal voltage output:


  • 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 does not decrease to below 0.21 V

  • (b) Heated oxygen sensor voltage does not increase to higher than 0.59 V

  • Open or short in heated oxygen sensor (sensor 2) circuit


  • Heated oxygen sensor (sensor 2)

  • Heated oxygen sensor (sensor 2) heater

  • Air fuel ratio sensor (sensor 1)

  • Gas leaks from exhaust system

  • EGR valve assembly
P0137

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 below 0.21 V

  • (b) Target air fuel ratio rich

  • Open or short in heated oxygen sensor (sensor 2)


  • Heated oxygen sensor (sensor 2)

  • Heated oxygen sensor (sensor 2) heater

  • Air fuel ratio sensor (sensor 1)

  • Gas leak from exhaust system

  • EGR valve assembly
P0138*

High voltage (short):


  • 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 higher than 0.59 V

  • (b) Target air fuel ratio lean

  • Short in heated oxygen sensor (sensor 2) circuit

  • Heated oxygen sensor (sensor 2)

  • Air fuel ratio sensor (sensor 1)

  • EGR valve assembly

  • ECM

Tech Tips

*: DTC P0136 and P0138 are for Euro-OBD only.

MONITOR DESCRIPTION


  1. 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 30 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.

  2. 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 decrease to below 0.21 V or does not increase to higher than 0.59 V during active air fuel ratio control, the ECM determines that the sensor voltage output is abnormal and sets DTCs P0136.

    A003ZRWE28

  3. Open or Short in Heated Oxygen Sensor Circuit (DTCs P0137 or P0138)

    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 or short, 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 below 0.21 V (lean), the ECM interprets this as an abnormally low sensor output voltage and stores DTC P0137. When the target air fuel ratio is lean and the voltage output is higher than 0.59 V (rich) during active air fuel ratio control, the ECM determines that the sensor voltage output is abnormally high, and stores DTC P0138.

    *: 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 Click here.

    A003VH0E25

TYPICAL ENABLING CONDITIONS

Heated Oxygen Sensor Output Voltage (Abnormal Voltage, High Voltage and Low Voltage)
Active air fuel ratio control Performing
Active air fuel ratio control begins when all of the following conditions are met: -
Auxiliary battery voltage 11 V or higher
Engine coolant temperature 75°C (167°F) or higher
Idling OFF
Engine speed Less than 4000 rpm
Air fuel ratio sensor status Activated
Fuel system status Closed loop
Engine load 10 to 70%

TYPICAL MALFUNCTION THRESHOLDS

Heated Oxygen Sensor Output Voltage (Abnormal Voltage)
Either of the following conditions is met: 1 or 2
1. Both of following conditions met (a) and (b)
(a) Commanded air fuel ratio 14.3 or less
(b) Heated oxygen sensor voltage 0.21 to 0.59 V
2. Both of following conditions met (c) and (d)
(c) Commanded air fuel ratio 14.9 or more
(d) Heated oxygen sensor voltage 0.21 to 0.59 V
Heated Oxygen Sensor Output Voltage (Low Voltage)
Both of following conditions met (a) and (b)
(a) Commanded air fuel ratio 14.3 or less
(b) Heated oxygen sensor voltage Below 0.21 V
Heated Oxygen Sensor Output Voltage (High Voltage)
Both of following conditions met (a) and (b)
(a) Commanded air fuel ratio 14.9 or more
(b) Heated oxygen sensor voltage Higher than 0.59 V

CONFIRMATION DRIVING PATTERN

A003VRJE34

  1. Connect the intelligent tester to the DLC3.

  2. Turn the power switch on (IG) and turn the tester on.

  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation).

  4. Turn the power switch off and wait for at least 30 seconds.

  5. Turn the power switch on (IG) and turn the tester on [A].

  6. Put the engine in inspection mode (maintenance mode) Click here.

  7. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher [B].

  8. Drive the vehicle at 75 to 120 km/h (47 to 75 mph) for 10 minutes or more [C].

    CAUTION:

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

  9. Enter the following menus: Powertrain / Engine and ECT / DTC [D].

  10. Read the pending DTC.

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

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

  12. Input the DTC: P0136, P0137 or P0138.

  13. Check the DTC judgment result.

    Tester 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
    UNKNOWN

    • Unable to perform DTC judgment

    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    Tech Tips


    • 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 UNKNOWN, perform steps [C] and [D] again.

WIRING DIAGRAM

A003XPAE02

INSPECTION PROCEDURE

Tech Tips

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 intelligent tester.


  1. Connect the intelligent tester to the DLC3.

  2. Turn the power switch on (IG) and turn the tester on.

  3. Put the engine in inspection mode (maintenance mode) Click here.

  4. Start the engine.

  5. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.

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

  7. Perform the Active Test operation with the engine in an idling.

  8. Monitor the voltage outputs of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2) displayed on the tester.

    Tech Tips


    • Change the fuel injection volume within the range of -12.0% to +12.0%. The injection volume can be changed in fine gradations.

    • Each sensor reacts in accordance with increases and decreases in the fuel injection volume.

    Tester Display (Sensor) Injection Volume Status Voltage

    AFS Voltage B1S1

    (Air fuel ratio)

    		 +12% Rich Less than 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 Less than 0.4 V

    Note

    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 A003XKYE17 A003XOUE06 -
    2 A003Y9IE11 A003XOUE06

    • Air fuel ratio sensor

    • Air fuel ratio sensor heater

    • Air fuel ratio sensor circuit
    3 A003XKYE17 A003Y9IE12

    • Heated oxygen sensor

    • Heated oxygen sensor heater

    • Heated oxygen sensor circuit

    • Exhaust gas leaks
    4 A003Y9IE11 A003Y9IE11

    • Fuel pressure

    • Exhaust gas leaks

      (Air fuel ratio extremely lean or rich)

    • 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 / All Data / AFS Voltage B1S1 and O2S B1S2.

Note

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

Tech Tips


  • If the OX1B wire from the ECM connector is short-circuited to the +B wire, DTC P0136 will be set.

  • Sensor 1 refers to the sensor closest to the engine assembly.

  • Sensor 2 refers to the sensor farthest away from the engine assembly.

  • Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.

PROCEDURE


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


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / DTC.

    5. Read the DTCs.

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

    B

    CHECK EXHAUST GAS LEAK Click here

    C

    PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE INJECTION VOLUME) Click here

    D

    GO TO DTC CHART Click here

    A

  2. READ VALUE USING INTELLIGENT TESTER (O2S B1S2)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

    5. Start the engine.

    6. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / O2S B1S2.

    7. Read the heated oxygen sensor output voltage while idling.

      Result
      Result Proceed to
      1.0 V or higher A
      Below 1.0 V B

    B

    PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE INJECTION VOLUME) Click here

    A

  3. INSPECT HEATED OXYGEN SENSOR (CHECK FOR SHORT)


    1. A003Y7WE04
      Text in Illustration
      *a

      Component without harness connected

      (Heated Oxygen Sensor (Sensor 2))

      Disconnect the heated oxygen sensor connector.

    2. 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) Always 10 kΩ or higher

    NG

    REPLACE HEATED OXYGEN SENSOR Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT)


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

    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
      D27-41 (HT1B) - D27-125 (OX1B) Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ECM Click here

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


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

    5. Start the engine and warm it up.

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

    7. Change the fuel injection volume using the tester and monitor the voltage output of air fuel ratio and heated oxygen sensors displayed on the tester.

      Tech Tips


      • Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine graduations within this range.

      • The air fuel ratio sensor is displayed as AFS Voltage B1S1, and the heated oxygen sensor is displayed as O2S B1S2 on the tester.

      • 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.

      • If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.

      Result
      Tester Display (Sensor) Voltage Variation Proceed to

      AFS Voltage B1S1

      (Air fuel ratio)

      		 Alternates between higher and below 3.3 V OK
      Remains at higher than 3.3 V NG
      Remains at below 3.3 V NG

      Tech Tips

      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 below or higher than 3.3 V despite the heated oxygen sensor indicating a normal reaction, the air fuel ratio sensor is malfunctioning.

      A003ZN0E08

    NG

    REPLACE AIR FUEL RATIO SENSOR NO.2 Click here

    OK

  6. INSPECT AIR FUEL RATIO SENSOR NO.2

    Tech Tips

    This air fuel ratio sensor test is to check the air fuel ratio sensor current during the fuel-cut. When the sensor is normal, the sensor current will indicate below 2.2 mA in this test.


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Put the engine in inspection mode (maintenance mode) Click here.

    6. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or more.

    7. Drive the vehicle at 75 km/h (47 mph) or more for 10 minutes or more.

      CAUTION:

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

    8. Stop the vehicle.

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

    10. Drive the vehicle at 75 km/h (47 mph) or more and decelerate the vehicle for 5 seconds or more. Perform this 3 times.

      CAUTION:

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

      A003YRJE26

    11. Read the value of the air fuel ratio sensor current while the fuel-cut operation is being performed.

      Standard current
      Below 2.2 mA

      Tech Tips


      • To measure the air fuel ratio sensor current precisely, perform the fuel-cut operation as long as possible.

      • If it is difficult to measure the air fuel ratio sensor current, use the snapshot function of the intelligent tester.


    OK

    REPLACE HEATED OXYGEN SENSOR Click here

    NG

    REPLACE AIR FUEL RATIO SENSOR NO.2 Click here

  7. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE INJECTION VOLUME)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

    5. Start the engine and warm it up.

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

    7. Change the fuel injection volume using the tester, monitoring the voltage output of the heated oxygen sensor displayed on the tester.

      Tech Tips


      • Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine graduations within this range.

      • 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
      Fluctuates between 0.4 V or less and 0.55 V or higher.

    NG

    CHECK EXHAUST GAS LEAK Click here

    OK

  8. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE INJECTION VOLUME)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

    5. Start the engine and warm it up.

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

    7. Change the fuel injection volume using the tester and monitor the voltage output of air fuel ratio and heated oxygen sensors displayed on the tester.

      Tech Tips


      • Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine graduations within this range.

      • The air fuel ratio sensor is displayed as AFS Voltage B1S1, and the heated oxygen sensor is displayed as O2S B1S2 on the tester.

      • 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.

      • If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.

      Result
      Tester Display (Sensor) Voltage Variation Proceed to

      AFS Voltage B1S1

      (Air fuel ratio)

      		 Alternates between higher and below 3.3 V OK
      Remains at higher than 3.3 V NG
      Remains at below 3.3 V NG

      Tech Tips

      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 below or higher than 3.3 V despite the heated oxygen sensor indicating a normal reaction, the air fuel ratio sensor is malfunctioning.

      A003ZN0E08

    NG

    REPLACE AIR FUEL RATIO SENSOR NO.2 Click here

    OK

  9. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE EGR STEP POSITION)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

    5. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

      Tech Tips

      The A/C switch and all accessory switches should be off.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Data List / All Data / Throttle Idle Position and MAP.

    7. Confirm that the Throttle Idle Position is ON and check the MAP value in the Data List while performing the Active Test.

      Note


      • Do not leave the EGR valve open for 10 seconds or more during the Active Test.

      • Be sure to return the EGR valve to step 0 when the Active Test is completed.

      • Do not open the EGR valve 30 steps or more during the Active Test.

      OK
      MAP change in response to EGR step position when Throttle Idle Position is ON in Data List.
      Standard
      - EGR Step Position (Active Test)
      0 Steps 0 to 30 Steps

      MAP

      (Data List)

      		 (EGR valve is fully closed) MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed

      Tech Tips


      • While performing the Active Test, if the increase in the value of MAP is small, the EGR valve assembly may be a malfunctioning.

      • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of MAP may occur while performing the Active Test. However, the amount that the value of MAP increases will be smaller than normal.

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

    B

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

    A

  10. INSPECT EGR VALVE ASSEMBLY


    1. Remove the EGR valve assembly Click here.

    2. Check if the EGR valve is stuck open.

      OK
      EGR valve is tightly closed.

    NG

    REPLACE EGR VALVE ASSEMBLY Click here

    OK

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

  11. CHECK EXHAUST GAS LEAK


    1. Check for exhaust gas leaks.

      OK
      No gas leaks.

    NG

    REPAIR OR REPLACE EXHAUST GAS LEAK POINT

    OK

  12. INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)


    1. Inspect the heated oxygen sensor Click here.


    NG

    REPLACE HEATED OXYGEN SENSOR Click here

    OK

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


    1. Disconnect the heated oxygen sensor 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
      D9-1 (HT1B) - D27-41 (HT1B) Always Below 1 Ω
      D9-3 (OX1B) - D27-125 (OX1B) Always Below 1 Ω
      D9-4 (E2) - D27-102 (O1B-) Always Below 1 Ω
      D9-1 (HT1B) or D27-41 (HT1B) - Body ground Always 10 kΩ or higher
      D9-3 (OX1B) or D27-125 (OX1B) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  14. REPLACE HEATED OXYGEN SENSOR


    1. Replace the heated oxygen sensor Click here.


    NEXT

  15. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the power switch off and wait for at least 30 seconds.

    6. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.


    NEXT

  16. CHECK WHETHER DTC OUTPUT RECURS (P0136, P0137 OR P0138)


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

    2. Input the DTCs: P0136, P0137 or P0138.

    3. Check the DTC judgment result is NORMAL. If it is INCOMPLETE, perform the drive pattern adding the vehicle speed.

      Result
      Result Proceed to

      ABNORMAL

      (DTC P0136, P0137 or P0138 is output)

      		 A

      NORMAL

      (DTC is not output)

      		 B

    B

    END

    A

  17. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE EGR STEP POSITION)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

    5. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

      Tech Tips

      The A/C switch and all accessory switches should be off.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Data List / All Data / Throttle Idle Position and MAP.

    7. Confirm that the Throttle Idle Position is ON and check the MAP value in the Data List while performing the Active Test.

      Note


      • Do not leave the EGR valve open for 10 seconds or more during the Active Test.

      • Be sure to return the EGR valve to step 0 when the Active Test is completed.

      • Do not open the EGR valve 30 steps or more during the Active Test.

      OK
      MAP change in response to EGR step position when Throttle Idle Position is ON in Data List.
      Standard
      - EGR Step Position (Active Test)
      0 Steps 0 to 30 Steps

      MAP

      (Data List)

      		 (EGR valve is fully closed) MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed

      Tech Tips


      • While performing the Active Test, if the increase in the value of MAP is small, the EGR valve assembly may be a malfunctioning.

      • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of MAP may occur while performing the Active Test. However, the amount that the value of MAP increases will be smaller than normal.

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

    B

    REPLACE AIR FUEL RATIO SENSOR NO.2 Click here

    A

  18. INSPECT EGR VALVE ASSEMBLY


    1. Remove the EGR valve assembly Click here.

    2. Check if the EGR valve is stuck open.

      OK
      EGR valve is tightly closed.

    NG

    REPLACE EGR VALVE ASSEMBLY Click here

    OK

    REPLACE AIR FUEL RATIO SENSOR NO.2 Click here

  19. REPLACE AIR FUEL RATIO SENSOR NO.2


    1. Replace the air fuel ratio sensor Click here.


    NEXT

  20. PERFORM CONFIRMATION DRIVING PATTERN


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Clear the DTCs Click here.

    5. Turn the power switch off and wait for at least 30 seconds.

    6. Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.


    NEXT

  21. CHECK WHETHER DTC OUTPUT RECURS (DTC P0136 OR P0138)


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

    2. Input the DTCs: P0136 or P0138.

    3. Check the DTC judgment result is NORMAL. If it is INCOMPLETE, perform the driving pattern again and increase the vehicle speed.

      Result
      Result Proceed to

      ABNORMAL

      (DTC P0136 or P0138 is output)

      		 A

      NORMAL

      (DTC is not output)

      		 B

    B

    END

    A

  22. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE EGR STEP POSITION)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the tester on.

    4. Put the engine in inspection mode (maintenance mode) Click here.

    5. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

      Tech Tips

      The A/C switch and all accessory switches should be off.

    6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Data List / All Data / Throttle Idle Position and MAP.

    7. Confirm that the Throttle Idle Position is ON and check the MAP value in the Data List while performing the Active Test.

      Note


      • Do not leave the EGR valve open for 10 seconds or more during the Active Test.

      • Be sure to return the EGR valve to step 0 when the Active Test is completed.

      • Do not open the EGR valve 30 steps or more during the Active Test.

      OK
      MAP change in response to EGR step position when Throttle Idle Position is ON in Data List.
      Standard
      - EGR Step Position (Active Test)
      0 Steps 0 to 30 Steps

      MAP

      (Data List)

      		 (EGR valve is fully closed) MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed

      Tech Tips


      • While performing the Active Test, if the increase in the value of MAP is small, the EGR valve assembly may be a malfunctioning.

      • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of MAP may occur while performing the Active Test. However, the amount that the value of MAP increases will be smaller than normal.

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

    B

    REPLACE HEATED OXYGEN SENSOR Click here

    A

  23. INSPECT EGR VALVE ASSEMBLY


    1. Remove the EGR valve assembly Click here.

    2. Check if the EGR valve is stuck open.

      OK
      EGR valve is tightly closed.

    NG

    REPLACE EGR VALVE ASSEMBLY Click here

    OK

    REPLACE HEATED OXYGEN SENSOR Click here