2GR-FKS (ENGINE CONTROL): SFI SYSTEM: P042000,P043000; Catalyst System Efficiency Below Threshold Bank 1; 2018 - 2020 MY Sienna [11/2017

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 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 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 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.

CATALYST LOCATION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

MONITOR RESULT

P0420: Catalyst Efficiency / O2 STORAGE B1

P0430: Catalyst Efficiency / O2 STORAGE B2

CONFIRMATION DRIVING PATTERN

Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON and turn the Techstream on.
Enter the following menus: Powertrain / Engine / Monitor / Current Monitor.
Check that Catalyst Efficiency / Current is Incomplete.
Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher [A].
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.
With the shift lever in S, 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.
Enter the following menus: Powertrain / Engine / Monitor / Current Monitor / O2 Sensor / RL F/C B1S2, RL F/C B2S2 [D].
Check the Test Value for RL F/C B1S2, RL F/C B2S2.
- 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.
Turn the ignition switch off and wait for at least 30 seconds [F].
Turn the ignition switch to ON and turn the Techstream on.
Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or higher [G].
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.
Enter the following menus: Powertrain / Engine / Trouble Codes [I].
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 battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.
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.
Enter the following menus: Powertrain / Engine / Trouble Codes [K].
Check if any DTCs are stored.
HINT:

If the monitor item does not change to Complete, and no DTCs are stored, drive the vehicle again under an increased load.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
Input the DTC: P042000 or P043000.

Check the DTC judgment result.

Techstream 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 battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

CONDITIONING FOR SENSOR TESTING

Perform the operation with the engine speeds and time durations described below prior to checking the waveforms of the air fuel ratio and heated oxygen sensors. This is to activate the sensors sufficiently to obtain appropriate inspection results.

Connect the Techstream to the DLC3.
Turn the ignition switch to ON and turn the Techstream on [A].
Start the engine and warm it up with all the accessories switched off until the engine coolant temperature stabilizes [B].
Enter the following menus: Powertrain / Engine / Data List / A/F (O2) Sensor Voltage B1S1 and O2 Sensor Voltage B1S2 or A/F (O2) Sensor Voltage B2S1 and O2 Sensor Voltage B2S2.
Run the engine at an engine speed of between 2500 rpm and 3000 rpm for at least 3 minutes [C].
While running the engine at 3000 rpm for 2 seconds, and then 2000 rpm for 2 seconds, check the waveforms of the air fuel ratio and heated oxygen sensors using the Techstream [D].

CAUTION / NOTICE / HINT

HINT:

If a malfunction cannot be found when troubleshooting DTC P042000 or P043000, a lean or rich abnormality may be the cause. Perform troubleshooting by following the inspection procedure for P017100 or P017400 (System Too Lean), and P017200 or P017500 (System Too Rich).
Bank 1 refers to the bank that includes the No. 1 cylinder*.
*: The No. 1 cylinder is the cylinder which is farthest from the transaxle.
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.
Read freeze frame data using the 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 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

If any DTCs other than P042000 and/or P043000 are output, troubleshoot those DTCs first.

(e) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / Data List / A/F (O2) Sensor Voltage B1S1 and O2 Sensor Voltage B1S2 or A/F (O2) Sensor Voltage B2S1 and O2 Sensor Voltage B2S2.

(f) Perform the Active Test operation with the engine idling (change the fuel injection volume).

(g) Monitor the voltage outputs of the air fuel ratio sensor and heated oxygen sensor (A/F (O2) Sensor Voltage B1S1 and O2 Sensor Voltage B1S2 or A/F (O2) Sensor Voltage B2S1 and O2 Sensor Voltage B2S2) displayed on the Techstream.

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

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

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

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