P0430

4GR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0420, P0430: Catalyst System Efficiency Below Threshold (Bank 1)
P0430 - Catalyst System Efficiency Below Threshold (Bank 2)

MONITOR DESCRIPTION

The ECM uses 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, sends pre-catalyst information to the ECM. The second sensor, the heated oxygen sensor, 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 voltage output of the heated oxygen sensor 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 15 to 20 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 heated oxygen sensor is long, the oxygen storage capacity is great. There is a direct correlation between the heated oxygen sensor 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 illuminates the MIL and sets the 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.





CATALYST LOCATION





NOTICE:
- When outputting DTC P0420 replace the exhaust manifold sub-assembly RH and the front exhaust pipe assembly together when catalyst replacement is necessary (Excluding air fuel ratio sensor and heated oxygen sensor).
- When outputting DTC P0430 replace the exhaust manifold sub-assembly LH and the front exhaust pipe assembly together when catalyst replacement is necessary (Excluding air fuel ratio sensor and heated oxygen sensor).

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





MONITOR RESULT

Refer to Checking Monitor Status Mode 6 Data.

CONFIRMATION DRIVING PATTERN

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 Techstream to the DLC3.

2. Turn the engine switch on (IG).

3. Turn the Techstream on.

4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation) Reading and Clearing Diagnostic Trouble Codes.

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

6. Turn the engine switch on (IG) and turn the Techstream on.

7. Enter the following menus: Powertrain / Engine / Monitor / Current Monitor.

8. Check that Catalyst Efficiency / Current is Incomplete.

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

10. 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.
- The monitor item will change to Complete as the Catalyst Efficiency monitor operates [C].

11. Enter the following menus: Powertrain / Engine / Trouble Codes.

12. Check if any DTCs (pending DTCs) are stored.

HINT
If the monitor item does not change to Complete, and no pending DTCs are stored, perform the following procedure.

13. Drive the vehicle at a speed between 75 and 100 km/h (47 and 62 mph) for 10 minutes or more [D].

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 [E].

14. Enter the following menus: Powertrain / Engine / Trouble Codes.

15. Check if any DTCs (pending DTCs) are stored.

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

16. If no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.

CONDITIONING FOR SENSOR TESTING

HINT
Perform the operation with the engine speeds and time durations described below prior to checking the waveforms of the A/F and HO2 sensors. This is in order to activate the sensors sufficiently to obtain the appropriate inspection results.





1. Connect the Techstream to the DLC3 [A].

2. Start the engine and warm it up with all the accessories switched off, until the engine coolant temperature stabilizes [B].

3. Run the engine at an engine speed of between 2500 rpm and 3000 rpm for at least 3 minutes [C].

4. While running the engine at 3000 rpm and 2000 rpm for 2 seconds, check the waveforms of the air fuel ratio and heated oxygen sensors using the Techstream [D].

HINT
- If either of the voltage outputs of either the air fuel ratio or heated oxygen sensor does not fluctuate, or either of the sensors makes a noise, the sensor may be malfunctioning.
- If the voltage outputs of both the sensors remain lean or rich, the air fuel ratio may be extremely lean or rich. In such cases, perform the Control the Injection Volume Active Test using the Techstream.
- If the three-way catalytic converter has deteriorated, the heated oxygen sensor (located behind the three-way catalytic converter) voltage output fluctuates up and down frequently, even under normal driving conditions (active air fuel ratio control is not performed).





INSPECTION PROCEDURE

HINT
- Read freeze frame data using Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction Freeze Frame Data.
- Bank 1 refers to the bank that includes the No. 1 cylinder*.
*: The No. 1 cylinder is the cylinder which is farthest from the transmission.
- Bank 2 refers to the bank that does not include the No. 1 cylinder.
- Sensor 1 refers to the sensor closest to the engine assembly.
- Sensor 2 refers to the sensor farthest away from the engine assembly.

PROCEDURE

1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0420 AND/OR P0430)

(a) Connect Techstream to the DLC3.

(b) Turn the engine switch on (IG) and turn the Techstream on.

(c) Enter the following menus: Powertrain / Engine / Trouble Codes.

(d) Read the DTCs.

Result:





HINT
If any DTCs other than P0420 and/or P0430 are output, troubleshoot those DTCs first.

B -- GO TO DTC CHART SFI System
A -- Continue to next step.

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

(a) Connect the Techstream to the DLC3.

(b) Start the engine and warm it up.

(c) Turn the Techstream on.

(d) Run the engine at an engine speed of 2500 rpm for approximately 90 seconds.

(e) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume / AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2.

(f) Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).

(g) Monitor the voltage outputs of the air fuel ratio sensor and heated oxygen sensor (AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2) displayed on the Techstream.

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

Standard:





Result:





Lean: During Control the Injection Volume, the air fuel ratio sensor output voltage (AFS Voltage B1S1 or AFS Voltage B2S1) is consistently higher than 3.4 V, and the heated oxygen sensor output voltage (O2S B1S2 or O2S B2S2) is consistently below 0.4 V.

Rich: During Control the Injection Volume, the AFS Voltage B1S1 or AFS Voltage B2S1 is consistently below 3.1 V, and the O2S B1S2 or O2S B2S2 is consistently higher than 0.55 V.

Lean/Rich: During Control the Injection Volume of the Active Test, the output voltage of the air fuel ratio sensor and heated oxygen sensor alternate correctly.

B -- REPLACE AIR FUEL RATIO SENSOR

C -- CHECK FOR EXHAUST GAS LEAK

D -- CHECK FOR EXHAUST GAS LEAK
A -- Continue to next step.

3. CHECK FOR EXHAUST GAS LEAK

(a) Check for exhaust gas leaks.

OK:

No gas leakage.

NG -- REPAIR OR REPLACE EXHAUST GAS LEAK POINT
OK -- Continue to next step.

4. CHECK DTC OUTPUT (DTC P0420 AND/OR P0430)

NOTICE:
- When outputting DTC P0420 replace the exhaust manifold sub-assembly RH (TWC: Front catalyst) and the front exhaust pipe assembly (TWC: Rear catalyst) together when catalyst replacement is necessary.
- When outputting DTC P0430 replace the exhaust manifold sub-assembly LH (TWC: Front catalyst) and the front exhaust pipe assembly (TWC: Rear catalyst) together when catalyst replacement is necessary.

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

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Trouble Codes.

(e) Read the DTCs.

Result:





A -- REPLACE EXHAUST MANIFOLD SUB-ASSEMBLY RH (TWC: FRONT CATALYST) Components

B -- REPLACE EXHAUST MANIFOLD SUB-ASSEMBLY LH (TWC: FRONT CATALYST) Components

C -- REPLACE FRONT EXHAUST PIPE ASSEMBLY (TWC: REAR CATALYST) Components

5. CHECK FOR EXHAUST GAS LEAK

(a) Check for exhaust gas leaks.

OK:

No gas leaks.

OK -- REPLACE HEATED OXYGEN SENSOR

NG -- REPAIR OR REPLACE EXHAUST GAS LEAK POINT

6. CHECK FOR EXHAUST GAS LEAK

(a) Check for exhaust gas leaks.

OK:

No gas leaks.

OK -- CHECK CAUSE OF EXTREMELY RICH OR LEAN ACTUAL AIR FUEL RATIO

NG -- REPAIR OR REPLACE EXHAUST GAS LEAK POINT

7. REPLACE AIR FUEL RATIO SENSOR

(a) Replace the air fuel ratio sensor Removal.

NEXT -- CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

8. REPAIR OR REPLACE EXHAUST GAS LEAK POINT

(a) Repair or replace exhaust gas leak point.

NEXT -- CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

9. REPLACE HEATED OXYGEN SENSOR

(a) Replace the heated oxygen sensor Removal.

NEXT -- CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

10. 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 P0171 Inspection Procedure P0171.

NEXT -- Continue to next step.

11. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(e) Turn the engine switch off and wait for at least 30 seconds.

(f) Start the engine.

(g) Turn the Techstream on.

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

(i) Enter the following menus: Powertrain / Engine / Trouble Codes.

(j) Read the pending DTCs.

Result:





B -- END
A -- Continue to next step.

12. CHECK DTC OUTPUT (DTC P0420 AND/OR P0430)

NOTICE:
- When outputting DTC P0420 replace the exhaust manifold sub-assembly RH (TWC: Front catalyst) and the front exhaust pipe assembly (TWC: Rear catalyst) together when catalyst replacement is necessary.
- When outputting DTC P0430 replace the exhaust manifold sub-assembly LH (TWC: Front catalyst) and the front exhaust pipe assembly (TWC: Rear catalyst) together when catalyst replacement is necessary.

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

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine / Trouble Codes.

(e) Read the DTCs.

Result:





A -- REPLACE EXHAUST MANIFOLD SUB-ASSEMBLY RH (TWC: FRONT CATALYST) Components

B -- REPLACE EXHAUST MANIFOLD SUB-ASSEMBLY LH (TWC: FRONT CATALYST) Components

C -- REPLACE FRONT EXHAUST PIPE ASSEMBLY (TWC: REAR CATALYST) Components