Toyota Corolla Cross: Catalyst System Efficiency Below Threshold Bank 1 (P042000)

MONITOR DESCRIPTION

The ECM uses air fuel ratio sensors mounted in front of and behind the Three-Way Catalytic Converter (TWC) to monitor its efficiency.

The first sensor, the air fuel ratio sensor (sensor 1), sends pre-catalyst information to the ECM. The second sensor, the air fuel ratio sensor (sensor 2), sends post-catalyst information to the ECM.

In order to detect any deterioration in the three-way catalytic converter, the ECM calculates the oxygen storage capacity of the three-way catalytic converter. This calculation is based on the output current of the air fuel ratio sensor (sensor 2) while performing active air fuel ratio control.

The oxygen storage capacity value is an indication of the oxygen storage capacity of the three-way catalytic converter. When the vehicle is being driven with a warm engine, active air fuel ratio control is performed for approximately 30 seconds. When it is performed, the ECM deliberately sets the air fuel ratio to lean or rich levels. If the cycle of the waveform for the air fuel ratio sensor (sensor 2) is long, the oxygen storage capacity is great. There is a direct correlation between the air fuel ratio sensor (sensor 2) and the oxygen storage capacity of the three-way catalytic converter.

The ECM uses the oxygen storage capacity value to determine the state of the three-way catalytic converter. If any deterioration has occurred, the ECM will illuminate the MIL and store a DTC.

This system determines the deterioration of the entire catalyst system (including the front and rear catalysts), by using the oxygen storage capacity value of the front catalyst, that is more sensitive than the rear catalyst, as the representative value. Therefore, be sure to replace the front and rear catalysts together when catalyst replacement is necessary.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Note
P042000	Catalyst System Efficiency Below Threshold Bank 1	The oxygen storage capacity value is less than the standard value under active air fuel ratio control (1 trip detection logic: except Mexico Models, 2 trip detection logic: for Mexico Models).	Gas leak from exhaust system Air fuel ratio sensor (sensor 1) Air fuel ratio sensor (sensor 2) Exhaust manifold (TWC: Front catalyst) Front exhaust pipe assembly (TWC: Rear catalyst) EGR valve assembly	Comes on	SAE Code: P0420 DTC for Mexico Models: Applies

CATALYST LOCATION

*A	for 2WD	*B	for AWD
*1	Air Fuel Ratio Sensor (Sensor 1)	*2	Air Fuel Ratio Sensor (Sensor 2)
*3	Exhaust Manifold	*4	Front Exhaust Pipe Assembly
*5	Tail Exhaust Pipe Assembly	*6	TWC: Front Catalyst
*7	TWC: Rear Catalyst	-	-

NOTICE:

When replacing the exhaust manifold (*3) and the front exhaust pipe assembly (*4) in order to replace the three-way catalytic converter, it is not necessary to replace the air fuel ratio sensor (sensor 1) (*1) and the air fuel ratio sensor (sensor 2) (*2).

MONITOR STRATEGY

Related DTCs	P0420: Catalyst deterioration
Required Sensors/Components (Main)	Air fuel ratio sensor (sensor 1) Air fuel ratio sensor (sensor 2)
Required Sensors/Components (Related)	Intake air temperature sensor Mass air flow meter sub-assembly Crankshaft position sensor Engine coolant temperature sensor
Frequency of Operation	Once per driving cycle
Duration	About 30 seconds
MIL Operation	1 driving cycle: except Mexico Models 2 driving cycles: for Mexico Models
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever the following DTCs are not stored	P0010, P1360, P1362, P1364, P1366, P2614 (Motor drive VVT system control module) P0011 (VVT system - advance) P0012 (VVT system - retard) P0013 (Exhaust VVT oil control solenoid) P0014 (Exhaust VVT system - advance) P0015 (Exhaust VVT system - retard) P0016 (VVT system - misalignment) P0017 (Exhaust VVT system - misalignment) P0031, P0032, P101D (Air fuel ratio sensor (sensor 1) heater) P0037, P0038, P102D (Air fuel ratio sensor (sensor 2) heater) P005D, P014C, P014D, P015A, P015B, P2195, P2196, P2237, P2238, P2239, P2252, P2253, P2A00 (Air fuel ratio sensor (sensor 1)) P0087, P0088, P0191, P0192, P0193 (Fuel pressure sensor (for high pressure side)) P0101, P0102, P0103 (Mass air flow meter) P0106, P0107, P0108 (Manifold absolute pressure) P0111, P0112, P0113 (Intake air temperature sensor) P0116, P0117, P0118 (Engine coolant temperature sensor) P0121, P0122, P0123, P0222, P0223, P2135 (Throttle position sensor) P0125 (Insufficient coolant temperature for closed loop fuel control) P0128 (Thermostat) P0136, P013A, P2270, P2271, P22AB, P22AC, P22AD, P22B3, P22B4 (Air fuel ratio sensor (sensor 2)) P0171, P0172 (Fuel system) P0201, P0202, P0203, P0204, P062D, P21CF, P21D0, P21D1, P21D2 (Fuel injector) P0300, P0301, P0302, P0303, P0304 (Misfire) P0327, P0328 (Knock control sensor) P0335, P0337, P0338 (Crankshaft position sensor) P0340, P0342, P0343 (Camshaft position sensor) P0365, P0367, P0368 (Exhaust camshaft position sensor) P0400 (EGR system) P0401 (EGR system (closed)) P0443 (EVAP system) P0489, P0490 (EGR control circuit) P0500 (Vehicle speed sensor) P0657, P0658, P2102, P2103, P2111, P2112, P2119 (Throttle actuator) P107B, P107C, P107D (Fuel pressure sensor (for low pressure side)) P11EA, P11EC, P11ED, P11EE, P11EF, P219A, P219C, P219D, P219E, P219F (Air-fuel ratio imbalance) P1235 (High pressure fuel pump circuit) P2228, P2229 (Atmospheric pressure sensor)
Response rate during fuel cut from rich condition	Completed
Auxiliary battery voltage	11 V or higher
Intake air temperature	-10°C (14°F) or higher
Engine coolant temperature	75°C (167°F) or higher
Atmospheric pressure	76 kPa(abs) [11 psi(abs)] or higher
Idling	Off
Engine speed	Less than 3200 rpm
Sub feedback control	Executing
Air fuel ratio sensor (sensor 1) status	Activated
Fuel system status	Closed loop
Engine load	10% or higher, and less than 100%
All of the following conditions are met	1, 2 and 3
1. Mass air flow	6 gm/sec or more, and less than 75 gm/sec
2. Front catalyst temperature (estimated)	580°C (1076°F) or higher, and less than 800°C (1472°F)
3. Rear catalyst temperature (estimated)	490°C (914°F) or higher, and less than 700°C (1292°F)
Shift position	3rd or higher

TYPICAL MALFUNCTION THRESHOLDS

Except Mexico Models

Oxygen Storage Capacity (OSC) of catalyst (Normalized)

Less than 1

For Mexico Models

Oxygen Storage Capacity (OSC) of catalyst (Normalized)

Less than 0.065

MONITOR RESULT

Refer to detailed information in Checking Monitor Status.

Click here

P0420: Catalyst Efficiency / O2 STORAGE B1

Monitor ID	Test ID	Scaling	Unit	Description
$21	$AF	Multiply by 0.001	No dimension	Oxygen storage capacity of catalyst bank 1 (Normalization)

CONFIRMATION DRIVING PATTERN

except Mexico Models

HINT:

• It is necessary for the response of the air fuel ratio sensor (sensor 2) to be normal in order to confirm DTC P042000. Therefore, perform the confirmation driving pattern for the air fuel ratio sensor (sensor 2) monitor before performing the confirmation driving pattern for the catalyst efficiency monitor.
• Performing this confirmation driving pattern will activate the catalyst efficiency monitor. This is very useful for verifying the completion of a repair.
• After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

  Click here

• When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

  Click here

1. Connect the GTS to the DLC3.
2. Turn the ignition switch to ON.
3. Turn the GTS on.
4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
5. Turn the ignition switch off and wait for at least 30 seconds.
6. Turn the ignition switch to ON.
7. Turn the GTS on.
8. Enter the following menus: Powertrain / Engine / Monitor / Current Monitor.
9. Check that Catalyst Efficiency / Current is Incomplete.
10. Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher with the shift lever in P [A].

    HINT:

    In order to keep the idle stable, turn the A/C and all other electric loads off and do not perform any shift operations.

11. Drive the vehicle at approximately 60 km/h (37 mph) for 10 minutes or more [B].

    CAUTION:

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

    HINT:

    Drive the vehicle while keeping the engine load as constant as possible.

12. With the shift lever in M or 2nd gear, 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.

13. Enter the following menus: Powertrain / Engine / Monitor / Current Monitor / O2 Sensor / Details / SLOW RESPONSE B1S2 [D].
14. Check the Test Value for SLOW RESPONSE B1S2.

    HINT:

    • If Test Value displays a value larger than 0, perform the following procedure, as the O2 Sensor monitor is finished.
    • If Test Value displays 0, perform step [C] until it displays a value larger than 0, as the O2 Sensor monitor is not finished.
15. Turn the ignition switch off and wait for at least 30 seconds [F].
16. Turn the ignition switch to ON.
17. Turn the GTS on.
18. Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher [G].
19. Drive the vehicle at approximately 60 km/h (37 mph) for 10 minutes or more [H].

    CAUTION:

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

    HINT:

    • Drive the vehicle while keeping the engine load as constant as possible.
    • The monitor item will change to Complete as the Catalyst Efficiency monitor operates.
20. Enter the following menus: Powertrain / Engine / Trouble Codes [I].
21. Check if any DTCs are stored.

    HINT:

    • If the monitor item does not change to Complete, and no DTCs are stored, perform the following procedure.
    • [A] to [I]: Normal judgment procedure.

      The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

    • When clearing the permanent DTCs, do not disconnect the cable from the auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
22. Drive the vehicle at a speed between 75 and 100 km/h (47 and 62 mph) for 10 minutes or more [J].

    CAUTION:

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

    HINT:

    • Drive the vehicle while keeping the engine load as constant as possible.
    • The monitor item will change to Complete as the Catalyst Efficiency monitor operates.
23. Enter the following menus: Powertrain / Engine / Trouble Codes [K].
24. Check if any DTCs are stored.

    HINT:

    If the monitor item does not change to Complete, and no DTCs are stored, extend the driving time.

25. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
26. Input the DTC: P042000.
27. Check the DTC judgment result.

    GTS Display	Description
    NORMAL	DTC judgment completed System normal
    ABNORMAL	DTC judgment completed System abnormal
    INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions

    HINT:

    • If the judgment result is NORMAL, the system is normal.
    • If the judgment result is ABNORMAL, the system has a malfunction.
    • [A] to [K]: Normal judgment procedure.

      The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

    • When clearing the permanent DTCs, do not disconnect the cable from the auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

for Mexico Models

HINT:

Performing this confirmation driving pattern will activate the catalyst efficiency monitor. This is very useful for verifying the completion of a repair.

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

   CAUTION:

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

   HINT:

   Drive the vehicle while keeping the engine load as constant as possible.

10. Turn the ignition switch off and wait for at least 30 seconds [C].
11. Turn the ignition switch to ON.
12. Turn the GTS on.
13. Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher [D].
14. Drive the vehicle at approximately 60 km/h (37 mph) for 10 minutes or more [E].

    CAUTION:

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

    HINT:

    Drive the vehicle while keeping the engine load as constant as possible.

15. Enter the following menus: Powertrain / Engine / Trouble Codes [F].
16. Read the pending DTCs.

    HINT:

    • If a pending DTC is output, the system is malfunctioning.
    • If a pending DTC is not output, perform the following procedure.
17. Drive the vehicle at a speed between 75 and 100 km/h (47 and 63 mph) for 10 minutes or more [G].

    CAUTION:

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

    HINT:

    Drive the vehicle while keeping the engine load as constant as possible.

18. Enter the following menus: Powertrain / Engine / Utility / All Readiness [H].
19. Input the DTC: P042000.
20. Check the DTC judgment result.

    GTS Display	Description
    NORMAL	DTC judgment completed System normal
    ABNORMAL	DTC judgment completed System abnormal
    INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system has a malfunction.
    • [A] to [H]: Normal judgment procedure.

      The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

    • When clearing the permanent DTCs, do not disconnect the cable from the auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

CAUTION / NOTICE / HINT

HINT:

• If a malfunction cannot be found when troubleshooting DTC P042000, a lean or rich abnormality may be the cause. Perform troubleshooting by following the inspection procedure for P017100 (System Too Lean) and P017200 (System Too Rich).
• 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 GTS. 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.	CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P042000)

(a) Read the DTCs.

Powertrain > Engine > Trouble Codes

Result	Proceed to
DTC P042000 is output	A
DTC P042000 and other DTCs are output	B

HINT:

If any DTCs other than P042000 are output, troubleshoot those DTCs first.

B

GO TO DTC CHART

A

2.	READ FREEZE FRAME DATA (LONG FT B1S2)

(a) Using the GTS, read the value displayed in the Freeze Frame Data.

Powertrain > Engine > DTC(P042000) > Freeze Frame Data

Tester Display
Long FT B1S2

GTS Display	Result	Proceed to
Long FT B1S2	Less than 1.0%	A
	1.0% or higher	B

B

GO TO STEP 18

A

3.	PERFORM ACTIVE TEST USING GTS (CONTROL THE INJECTION VOLUME FOR A/F SENSOR)

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

(b) Warm up the air fuel ratio sensors at an engine speed of 2500 rpm for 90 seconds.

(c) Enter the following menus.

Powertrain > Engine > Active Test

Active Test Display
Control the Injection Volume for A/F Sensor

Data List Display
Coolant Temperature
A/F (O2) Sensor Current B1S1
A/F (O2) Sensor Current B1S2

(d) Change the fuel injection volume using the GTS, and monitor the output current of the air fuel ratio sensor (sensor 1) (A/F (O2) Sensor Current B1S1) and air fuel ratio sensor (sensor 2) (A/F (O2) Sensor Current B1S2) displayed on the GTS.

HINT:

• The Active Test "Control the Injection Volume for A/F Sensor" can be used to lower the fuel injection volume by 12.5% or increase the injection volume by 12.5%.
• The air fuel ratio sensor (sensor 1) is displayed as A/F (O2) Sensor Current B1S1, and the air fuel ratio sensor (sensor 2) is displayed as A/F (O2) Sensor Current B1S2 on the GTS.
• The air fuel ratio sensor (sensor 1) has an output delay of a few seconds and the air fuel ratio sensor (sensor 2) has a maximum output delay of approximately 20 seconds.
• If the sensor output current does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.

Standard:

GTS Display (Sensor)	Injection Volume	Status	Current
A/F (O2) Sensor Current B1S1 (Air fuel ratio (sensor 1))	12.5%	Rich	Below -0.075 mA
	-12.5%	Lean	More than 0.037 mA
A/F (O2) Sensor Current B1S2 (Air fuel ratio (sensor 2))	12.5%	Rich	Below -0.86 mA
	-12.5%	Lean	More than 0.33 mA

Status A/F (O2) Sensor Current B1S1	Status A/F (O2) Sensor Current B1S2	Actual air fuel ratio, air fuel ratio sensor (sensor 1) and air fuel ratio sensor (sensor 2) condition	Main Suspected Trouble Area	Proceed to
Lean/Rich	Lean/Rich	Normal	Three-way catalytic converter Gas leak from exhaust system EGR valve assembly	A
Lean	Lean/Rich	Air fuel ratio sensor (sensor 1) malfunction	Air fuel ratio sensor (sensor 1)	B
Rich	Lean/Rich	Air fuel ratio sensor (sensor 1) malfunction	Air fuel ratio sensor (sensor 1)
Lean/Rich	Lean	Air fuel ratio sensor (sensor 2) malfunction	Air fuel ratio sensor (sensor 2) Gas leak from exhaust system	C
Lean/Rich	Rich	Air fuel ratio sensor (sensor 2) malfunction	Air fuel ratio sensor (sensor 2) Gas leak from exhaust system
Lean	Lean	Actual air fuel ratio lean	Extremely lean actual air fuel ratio Gas leak from exhaust system EGR valve assembly	D
Rich	Rich	Actual air fuel ratio rich	Extremely rich actual air fuel ratio Gas leak from exhaust system EGR valve assembly

• Lean: During the Control the Injection Volume for A/F Sensor Active Test, the air fuel ratio sensor (sensor 1) output current (A/F (O2) Sensor Current B1S1) is consistently more than 0.037 mA, and the air fuel ratio sensor (sensor 2) output current (A/F (O2) Sensor Current B1S2) is consistently more than 0.33 mA.
• Rich: During the Control the Injection Volume for A/F Sensor Active Test, the air fuel ratio sensor (sensor 1) output current (A/F (O2) Sensor Current B1S1) is consistently below -0.075 mA, and the air fuel ratio sensor (sensor 2) output current (A/F (O2) Sensor Current B1S2) is consistently below -0.86 mA.
• Lean/Rich: During the Control the Injection Volume for A/F Sensor Active Test, the output current of the air fuel ratio sensor (sensor 1) or air fuel ratio sensor (sensor 2) alternate correctly.

HINT:

Refer to "Data List / Active Test" [A/F (O2) Sensor Current B1S1, A/F (O2) Sensor Current B1S2].

Click here

B

GO TO STEP 7

C

GO TO STEP 8

D

GO TO STEP 10

A

4.	CHECK FOR EXHAUST GAS LEAK

(a) Check for exhaust gas leaks.

OK:

No gas leaks in exhaust system.

NG

GO TO STEP 14

OK

5.	PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)

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

HINT:

The A/C switch and all accessories should be off.

(b) Enter the following menus.

Powertrain > Engine > Active Test

Active Test Display
Control the EGR Step Position

Data List Display
Engine Speed
Intake Manifold Absolute Pressure
Coolant Temperature

(c) Check the engine idling condition and Intake Manifold Absolute Pressure values in the Data List while performing the Active Test.

NOTICE:

• 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:

The value of Intake Manifold Absolute Pressure and Engine Speed change in response to EGR step position.

Standard:

-	Control the EGR Step Position (Active Test)
	0 Steps	0 to 30 Steps
Idling condition	Steady idling	Idling changes from steady to rough idling or engine stalls
Intake Manifold Absolute Pressure (Data List)	Intake Manifold Absolute Pressure value is 18 to 38 kPa(abs) (2.6 to 5.5 psi(abs)) (EGR valve is fully closed)	Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed

HINT:

During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in the EGR valve.

OK

GO TO STEP 17

NG

6.	INSPECT EGR VALVE ASSEMBLY

(a) Remove the EGR valve assembly.

Click here

(b) Check if the EGR valve is stuck open.

OK:

EGR valve is tightly closed.

HINT:

Perform "Inspection After Repair" after replacing the EGR valve assembly.

Click here

OK

GO TO STEP 17

NG

REPLACE EGR VALVE ASSEMBLY

7.	REPLACE AIR FUEL RATIO SENSOR (SENSOR 1)

Click here

HINT:

Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 1).

Click here

NEXT

GO TO STEP 15

8.	CHECK FOR EXHAUST GAS LEAK

(a) Check for exhaust gas leaks.

OK:

No gas leaks in exhaust system.

NG

GO TO STEP 14

OK

9.	REPLACE AIR FUEL RATIO SENSOR (SENSOR 2)

Click here

HINT:

Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 2).

Click here

NEXT

GO TO STEP 15

10.	CHECK FOR EXHAUST GAS LEAK

(a) Check for exhaust gas leaks.

OK:

No gas leaks in exhaust system.

NG

GO TO STEP 14

OK

11.	PERFORM ACTIVE TEST USING GTS (CONTROL THE EGR STEP POSITION)

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

HINT:

The A/C switch and all accessories should be off.

(b) Enter the following menus.

Powertrain > Engine > Active Test

Active Test Display
Control the EGR Step Position

Data List Display
Engine Speed
Intake Manifold Absolute Pressure
Coolant Temperature

(c) Check the engine idling condition and Intake Manifold Absolute Pressure values in the Data List while performing the Active Test.

NOTICE:

• 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:

The value of Intake Manifold Absolute Pressure and Engine Speed change in response to EGR step position.

Standard:

-	Control the EGR Step Position (Active Test)
	0 Steps	0 to 30 Steps
Idling condition	Steady idling	Idling changes from steady to rough idling or engine stalls
Intake Manifold Absolute Pressure (Data List)	Intake Manifold Absolute Pressure value is 18 to 38 kPa(abs) (2.6 to 5.5 psi(abs)) (EGR valve is fully closed)	Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed

HINT:

During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in the EGR valve.

OK

GO TO STEP 13

NG

12.	INSPECT EGR VALVE ASSEMBLY

(a) Remove the EGR valve assembly.

Click here

(b) Check if the EGR valve is stuck open.

OK:

EGR valve is tightly closed.

HINT:

Perform "Inspection After Repair" after replacing the EGR valve assembly.

Click here

NG

REPLACE EGR VALVE ASSEMBLY

OK

13.	CHECK CAUSE OF EXTREMELY RICH OR LEAN ACTUAL AIR FUEL RATIO

(a) Check the cause of extremely rich or lean actual air fuel ratio, referring to the DTC P017100 and P017200 Inspection Procedure.

Click here

NEXT

GO TO STEP 15

14.	REPAIR OR REPLACE EXHAUST SYSTEM

HINT:

Perform "Inspection After Repair" after repairing or replacing the exhaust system.

Click here

NEXT

15.

CLEAR DTC

(a) Clear the DTCs.

Powertrain > Engine > Clear DTCs

(b) Turn the ignition switch off and wait for at least 30 seconds.

NEXT

16.	CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

(a) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(b) Read the DTCs.

Powertrain > Engine > Trouble Codes

Result	Proceed to
DTCs are not output	A
DTC P042000 is output	B

A

END

B

17.	REPLACE EXHAUST MANIFOLD (TWC: FRONT CATALYST) AND FRONT EXHAUST PIPE ASSEMBLY (TWC: REAR CATALYST)

NOTICE:

When replacing the exhaust manifold and the front exhaust pipe assembly in order to replace the three-way catalytic converter, it is not necessary to replace the air fuel ratio sensor (sensor 1) and the air fuel ratio sensor (sensor 2).

HINT:

Confirm the replacement parts, referring to the illustration in the Catalyst Location.

(a) Replace the exhaust manifold (TWC: Front catalyst).

for 2WD: Click here

for AWD: Click here

(b) Replace the front exhaust pipe assembly (TWC: Rear catalyst).

for 2WD: Click here

for AWD: Click here

NEXT

END

18.	CHECK FOR EXHAUST GAS LEAK

OK:

No gas leaks in exhaust system.

HINT:

Perform "Inspection After Repair" after repairing or replacing the exhaust system.

Click here

NG

REPAIR OR REPLACE EXHAUST SYSTEM

OK

19.	REPLACE AIR FUEL RATIO SENSOR (SENSOR 2)

Click here

HINT:

Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 2).

Click here

NEXT

20.

CLEAR DTC

(a) Clear the DTCs.

Powertrain > Engine > Clear DTCs

(b) Turn the ignition switch off and wait for at least 30 seconds.

NEXT

21.	CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

(a) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(b) Check for DTCs.

Powertrain > Engine > Trouble Codes

DTCs are not output.

NEXT

END

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