Sfi System - P0158

1. Description

2. Monitor description

3. Monitor strategy

4. Typical enabling conditions

5. Typical malfunction thresholds

6. Component operating range

7. Monitor result

8. Wiring diagram

9. Confirmation driving pattern

10. Inspection procedure

11. Check other dtc output

12. Read value of intelligent tester (output voltage of heated oxygen sensor)

13. Check harness and connector (check for short)

14. Inspect heated oxygen sensor (check for short)

15. Perform confirmation driving pattern

16. Read output dtc (dtc p0138, p0158)

17. Read value of intelligent tester (output voltage of heated oxygen sensor)

18. Perform confirmation driving pattern

19. Read dtc output (dtc p0138, p0158)

20. Replace heated oxygen sensor

21. Perform confirmation driving pattern

22. Read dtc output (dtc p0138 or p0158)

23. Perform active test by intelligent tester (injection volume)

24. Check for exhaust gas leakage

25. Inspect heated oxygen sensor (heater resistance)

26. Inspect efi relay

27. Check harness and connector (ecm - heated oxygen sensor)

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 P0156 Oxygen Sensor Circuit Malfunction (Bank 2 Sensor 2)

DTC P0157 Oxygen Sensor Circuit Low Voltage (Bank 2 Sensor 2)

DTC P0158 Oxygen Sensor Circuit High Voltage (Bank 2 Sensor 2)

​

DESCRIPTION

HINT:

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

MONITOR DESCRIPTION

1. 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, one of the following DTCs is set: DTC P0136, P0156 (abnormal voltage output), P0137, P0157 (open circuit) and P0138, P0158 (short circuit).
   
2. Abnormal Voltage Output of HO2 Sensor (DTC P0136 and P0156)
   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 HO2 sensor voltage does nor decrease to less than 0.21 V and does not increase to more than 0.59 V during active air fuel ratio control, the ECM determines that the sensor voltage output is abnormal and sets DTC P0136.
   
   
   
   
   
   
3. Open or short in the Heated Oxygen (HO2) Sensor Circuit (DTC P0137, P0157, P0138 or P0158)
   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 HO2 sensor has an open or short, 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 HO2 sensor output does not change.
   While performing active air fuel ratio control, when the target air fuel ratio is rich and the HO2 sensor voltage output is 0.21 V or less (lean), the ECM interprets this as an abnormally low sensor output voltage and sets DTC P0137 or P0157. When the target air fuel ratio is lean and the voltage output is 0.59 V or more (rich) during active air fuel ratio control, the ECM determines that the sensor voltage output is abnormally high, and sets DTC P0138 or P0158.
   

   HINT:

   DTC P0138 or P0158 is also set if the HO2 sensor voltage output is more than 1.2 V for 30 seconds or more.

   *: 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).

   
   
   
   
   
   
4. High or Low Impedance of Heated Oxygen (HO2) Sensor (DTC P0136, P0156, P0137 or P0157)
   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 HO2 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.
   

   HINT:

   1. *: The effective resistance in an alternating current electrical circuit.
      
   2. The impedance cannot be measured using an ohmmeter.
      
   3. DTC P0136 or P0156 indicates the deterioration of the HO2 sensor. The ECM sets the DTC by calculating the impedance of the sensor when the typical enabling conditions are satisfied (1 driving cycle).
      
   4. DTC P0137 or P0157 indicates an open circuit in the HO2 sensor (1 driving cycle). The ECM sets this DTC when the impedance of the sensor exceeds the threshold 348.1 MΩ.
      

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

MONITOR RESULT

1. MID (Monitor Identification Data) is assigned to each emissions-related component.
   
2. TID (Test Identification Data) is assigned to each test value.
   
3. Scaling is used to calculate the test value indicated on generic OBD II scan tools.
   
   

   HO2S bank 1 sensor 2

   MID	TID	Scaling	Description of Test Value	Minimum Test Limit	Maximum Test Limit
   $02	$07	Multiply by 0.001 (V)	Minimum sensor voltage	Minimum test limit	Maximum test limit
   $02	$08	Multiply by 0.001 (V)	Maximum sensor voltage	Minimum test limit	Maximum test limit
   $02	$8F	Multiply by 0.001 (g)	Maximum oxygen storage capacity	0	Maximum test limit

   
   

   HO2S bank 2 sensor 2

   MID	TID	Scaling	Description of Test Value	Minimum Test Limit	Maximum Test Limit
   $06	$07	Multiply by 0.001 (V)	Minimum sensor voltage	Minimum test limit	Maximum test limit
   $06	$08	Multiply by 0.001 (V)	Maximum sensor voltage	Minimum test limit	Maximum test limit
   $06	$8F	Multiply by 0.001 (g)	Maximum oxygen storage capacity	0	Maximum test limit

WIRING DIAGRAM

CONFIRMATION DRIVING PATTERN

NOTICE:

This test will not be completed if the vehicle is driven under absolutely constant speed, such as with cruise control activated.

1. Connect the intelligent tester to the DLC3 with CAN VIM [A].
   
2. Turn the ignition switch ON [B].
   
3. Turn the tester ON [C].
   
4. Clear DTCs (if set) (Click here) [D].
   
5. Enter the following menus: DIAGNOSIS / CARB OBD II / READINESS TESTS [E].
   
6. Check that O2S EVAL is INCMPL (incomplete) [F].
   
7. Start the engine and warm it up [G].
   
8. Drive the vehicle at between 40 mph and 70 mph (64 km/h and 113 km/h) for at least 10 minutes [H].
   
9. Note the state of the Readiness Tests items. Those items will change to COMPL (complete) as O2S EVAL monitor operates [I].
   
10. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC INFO / PENDING CODES and check if any pending DTCs are set [J].
    

    HINT:

    If O2S EVAL does not change to COMPL, and any pending DTCs fail to set, extend the driving time.

INSPECTION PROCEDURE

HINT:

Intelligent tester only:

Malfunctioning areas can be identified by performing the A/F CONTROL function provided in the ACTIVE TEST. The A/F CONTROL function can help to determine whether the Air Fuel Ratio (A/F) sensor, Heated Oxygen (HO2) sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the A/F CONTROL operation using an intelligent tester.

1. Connect the intelligent tester to the DLC3 with CAN VIM.
   
2. Start the engine and turn the tester ON.
   
3. Warm up the engine at engine speed of 2,500 rpm for approximately 90 seconds.
   
4. On the tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F CONTROL.
   
5. Perform the A/F CONTROL operation with the engine in an idling condition (press the RIGHT or LEFT button to change the fuel injection volume).
   
6. Monitor the voltage outputs of the A/F and HO2 sensors (AFS B1S1 and O2S B1S2 or AFS B2S1 and O2S B2S2) displayed on the tester.
   

HINT:

1. The A/F CONTROL operation lowers the fuel injection volume by 12.5 % or increases the injection volume by 25 %.
   
2. Each sensor reacts in accordance with increases in the fuel injection volume.
   

NOTICE:

The Air Fuel Ratio (A/F) sensor has an output delay of a few seconds and the Heated Oxygen (HO2) sensor has a maximum output delay of approximately 20 seconds.

Case	A/F Sensor (Sensor 1) Output Voltage		HO2 Sensor (Sensor 2) Output Voltage		Main Suspected Trouble Area
1	Injection Volume +25 % -12.5 %		Injection Volume +25 % -12.5 %		-
	Output Voltage More than 3.35 V Less than 3.0 V		Output Voltage More than 0.55 V Less than 0.4 V
2	Injection Volume +25 % -12.5 %		Injection Volume +25 % -12.5 %		A/F sensor A/F sensor heater A/F sensor circuit
	Output Voltage Almost no reaction		Output Voltage More than 0.5 V Less than 0.4 V
3	Injection Volume +25 % -12.5 %		Injection Volume +25 % -12.5 %		HO2 sensor HO2 sensor heater HO2 sensor circuit
	Output Voltage More than 3.35 V Less than 3.0 V		Output Voltage Almost no reaction
4	Injection volume +25 % -12.5 %		Injection Volume +25 % -12.5 %		Fuel injector Fuel pressure Gas leakage from exhaust system (Air fuel ratio extremely lean or rich)
	Output Voltage Almost no reaction		Output Voltage Almost no reaction

1. Following the A/F CONTROL procedure enables technicians to check and graph the voltage outputs of both the A/F and HO2 sensors.
   
2. To display the graph, enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F CONTROL / USER DATA / AFS B1S1 and O2S B1S2 or AFS B2S1 and O2S B2S2. Then press the YES button and ENTER button, followed by the F4 button.
   

HINT:

1. If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
   
2. 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 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.
   
3. If the OX1B wire from the ECM connector is short-circuited to the +B wire, DTC P0136 will be set.
   
4. If the OX2B wire from the ECM connector is short-circuited to the +B wire, DTC P0156 will be set.
   

1. Connect the intelligent tester to the DLC3 with CAN VIM.

2. Turn the ignition switch ON and turn the tester ON.

3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.

4. Read DTCs.
   

   Result:

   
   

   Display (DTC Output)	Proceed to
   P0138 or P0158	A
   P0137 or P0157	B
   P0136 or P0156	C

B	Go to step 14
C	Go to step 7

A

1. Connect the intelligent tester to the DLC3 with CAN VIM.

2. After warming up the engine, run the engine at 2,500 rpm for 3 minutes.

3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / O2S B1S2 or O2S B2S2.

4. Allow the engine to idle.

5. Read the Heated Oxygen (HO2) sensor output voltage while idling.
   

   Result:

   
   

   HO2 Sensor Output Voltage	Proceed to
   More than 1.2 V	A
   Less than 1.0 V	B

B	Go to step 5

A

1. Turn the ignition switch OFF and wait for 5 minutes.

2. Disconnect the E4 and E5 ECM connectors.

3. Check the resistance.

   Standard resistance:

   Tester Connection	Specified Condition
   HT1B (E4-1) - OX1B (E4-18)	10 kΩ or higher
   HT2B (E5-5) - OX2B (E5-33)	10 kΩ or higher

4. Reconnect the ECM connector.

NG	Go to step 4

OK
REPLACE ECM

1. Disconnect the H6 or H8 Heated Oxygen (HO2) sensor connector.

2. Measure the resistance of the HO2 sensor connector.

   Standard resistance (Bank 1, 2 sensor 2):

   Tester Connection	Specified Condition
   HT (1) - +B (2)	11 to 16 Ω at 20°C (68°F)
   HT (1) - E1 (4)	10 kΩ or higher

3. Reconnect the HO2 sensor connector.

NG	REPLACE HEATED OXYGEN SENSOR

OK
REPAIR OR REPLACE HARNESS OR CONNECTOR

HINT:

Clear all DTCs prior to performing the confirmation driving pattern.

NEXT

1. Enter the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / PENDING CODES.

2. Read DTCs.
   

   Result:

   
   

   Display (DTC Output)	Proceed to
   No output	A
   P0136 and/or P0156	B

A	CHECK FOR INTERMITTENT PROBLEMS

B
REPLACE HEATED OXYGEN SENSOR

1. Connect the intelligent tester to the DLC3 with CAN VIM.

2. Turn the ignition switch ON and turn the tester ON.

3. Start the engine.

4. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / O2S B1S2.

5. After warming up the engine, run the engine at an engine speed of 2,500 rpm for 3 minutes.

6. Read the output voltage of the HO2 sensor when the engine rpm is suddenly increased.

   HINT:

   Quickly accelerate the engine to 4,000 rpm 3 times using the accelerator pedal.

   Standard voltage:

   Fluctuates between 0.4 V or less and 0.5 V or more.
   

NG	Go to step 14

OK

NEXT

1. On the intelligent tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC INFO / PENDING CODES.

2. Read DTCS.
   

   Result:

   
   

   Display (DTC Output)	Proceed to
   P0136 or P0156	A
   No output	B

B	CHECK FOR INTERMITTENT PROBLEMS

A

1. Replace HO2 sensor (Click here).

NEXT

NEXT

1. On the intelligent tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / DTC INFO / PENDING CODES.

2. Read DTCs.
   

   Result:

   
   

   Display (DTC Output)	Proceed to
   P0136 or P0156	A
   No output	B

B	REPLACE COMPLETED

A

1. Connect the intelligent tester to the DLC3 with CAN VIM.

2. Start the engine and turn the tester ON.

3. Warn up the engine.

4. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / INJ VOL.

5. Change the injection volume using the tester, monitoring the voltage output of Air Fuel Ratio (A/F) and HO2 sensors displayed on the tester.

   HINT:

   1. Change the fuel injection volume within the range of -12 % and +12 %. The injection volume can be changed in 1 % graduations within the range.
      
   2. The A/F sensor is displayed as AFS B1S1 (AFS B2S1), and the HO2 sensor is displayed as O2S B1S2 (O2S B2S2) on the intelligent tester.
      
   
   

   Result:

   
   

   Tester Display (Sensor)	Voltage Variations	Proceed to
   AFS B1S1 (AFS B2S1) (A/F)	Alternates between more than 3.3 V and less than 3.3 V	OK
   AFS B1S1 (AFS B2S1) (A/F)	Remains at more than 3.3 V	NG
   AFS B1S1 (AFS B2S1) (A/F)	Remains at less than 3.3 V	NG

   HINT:

   A normal HO2 sensor voltage (O2S B1S2 or O2S B2 S2) reacts in accordance with increases and decreases in fuel injection volumes. When the A/F sensor voltage remains at either less than 3.3 V or more than 3.3 V despite the HO2 sensor indicating a normal reaction, the A/F sensor is malfunctioning.

   
   
   
   

NG	REPLACE AIR FUEL RATIO SENSOR

OK
CHECK AND REPLACE EXTREMELY RICH OR LEAN ACTUAL AIR FUEL RATIO (FUEL INJECTOR, FUEL PRESSURE, GAS LEAKAGE FROM EXHAUST SYSTEM, ETC.)

1. Check for exhaust gas leakage from the exhaust manifold and pipe.

   OK:

   No exhaust gas leakage.
   

NG	REPAIR OR REPLACE EXHAUST GAS LEAKAGE POINT

OK

1. Disconnect the H6 or H8 HO2 sensor connector.

2. Measure the resistance of the HO2 sensor connector.

   Standard resistance (Bank 1, 2 sensor 2):

   Tester Connection	Specified Condition
   HT (1) - +B (2)	11 to 16 Ω at 20°C (68°F)
   HT (1) - E1 (4)	10 kΩ or higher

3. Reconnect the HO2 sensor connector.

NG	REPLACE HEATED OXYGEN SENSOR

OK

1. Remove the EFI relay from the engine room relay block.

2. Measure the resistance of the EFI relay.

   Standard resistance:

   Tester Connection	Specified Condition
   3 - 5	10 kΩ or higher
   3 - 5	Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

3. Reinstall the EFI relay.

NG	REPLACE EFI RELAY

OK

1. Disconnect the heated oxygen sensor connector.

2. Disconnect the E4 and E5 ECM connector.

3. Measure the resistance between the wire harness side connectors.

   Standard resistance:

   Tester Connection	Specified Condition
   OXL2 (H6-3) - OX1B (E4-18)	Below 1 Ω
   HTL2 (H6-1) - HT1B (E4-1)	Below 1 Ω
   OXR2 (H8-3) - OX2B (E5-33)	Below 1 Ω
   HTR2 (H8-1) - HT2B (E5-5)	Below 1 Ω
   OXL2 (H6-3) or OX1B (E4-18) - Body ground	10 kΩ or higher
   HTL2 (H6-1) or HT1B (E4-1) - Body ground	10 kΩ or higher
   OXR2 (H8-3) or OX2B (E5-33) Body ground	10 kΩ or higher
   HTR2 (H8-1) or HT2B (E5-5) - Body ground	10 kΩ or higher

   
   
   
   

NG	REPAIR OR REPLACE HARNESS OR CONNECTOR

OK
REPLACE HEATED OXYGEN SENSOR