P2443

1UR-FE ENGINE CONTROL: SFI SYSTEM: P2440-P2443: Secondary Air Injection System Switching Valve Stuck Open Bank1
P2443 - Secondary Air Injection System Switching Valve Stuck Closed Bank 2

DESCRIPTION

The secondary air injection system injects air into the exhaust port of the cylinder head using an electric air pump, starting when the engine is started cold and operating until the catalyst warms up, in order to promote combustion of unburned fuel and decrease the amount of hydrocarbons (HC) and carbon monoxide (CO) in the exhaust gas.









HINT
Air switching valve normal operation:

When the air switching valve is open, exhaust gas pulsation occurs in the secondary air passage.

When the air switching valve is closed, exhaust gas pulsation does not occur in the secondary air passage.

MONITOR DESCRIPTION

DTCs P2440 and P2442 indicate that the air switching valve is stuck open. DTCs P2441 and P2443 indicate that the air switching valve is stuck closed. The ECM performs diagnosis of the secondary air injection system based on the pressure pulsation when the system is not operating. If a malfunction is detected, the ECM illuminates the MIL and stores a DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

All





















P2440, P2442 Air Switching Valve is Stuck Open (Case 2)





TYPICAL MALFUNCTION THRESHOLDS

P2440 Air Switching Valve is Stuck Open (Case 1)





P2442 Air Switching Valve is Stuck Open (Case 1)





P2440, P2442 Air Switching Valve is Stuck Open (Case 2)





P2441 Air Switching Valve is Stuck Closed





P2443 Air Switching Valve is Stuck Closed





Secondary Air Injection ON (Condition 1)





Secondary Air Injection ON (Condition 2)





Secondary Air Injection ON (Condition 3)





Secondary Air Injection ON (Condition 4)





Secondary Air Injection OFF (Condition 1)





Secondary Air Injection OFF (Condition 2)





Secondary Air Injection OFF (Condition 3)





Secondary Air Injection OFF (Condition 4)





HINT
Refer to "Data List / Active Test" [Air Pump Pressure (Absolute), Air Pump2 Pressure (Absolute) and Air Pump Pulsation Pressure] Data List / Active Test.

MONITOR RESULT

Refer to Checking Monitor Status Mode 6 Data.

CONFIRMATION DRIVING PATTERN

NOTICE:
- This Air Injection Check only allows technicians to operate the secondary air injection system for a maximum of 5 seconds. Furthermore, the check can only be performed up to 4 times per trip. If the test is repeated, intervals of at least 30 seconds are required between checks. While secondary air injection system operation using the Techstream is prohibited, the Techstream display indicates the prohibition (WAIT or ERROR). If ERROR is displayed on the Techstream during the test, stop the engine for 10 minutes, and then try again.
- Performing Air Injection Check repeatedly may cause damage to the secondary air injection system. If it is necessary to repeat the check, leave an interval of several minutes between System Check operations to prevent the system from overheating.
- When performing the Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the engine switch turned on (IG) or the engine running.
- Turn the engine switch off when the Air Injection Check operation finishes.
- Start the engine and warm it up.

- Turn the engine switch off.

- Connect the Techstream to the DLC3.

- Turn the engine switch on (IG).

- Turn the Techstream on.

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

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

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

- Enter the following menus: Powertrain / Engine and ECT / Utility / Air injection check / Automatic Mode.

- Start the engine after the Techstream initialization is finished.

- Perform the System Check operation by pressing ENTER (Next).

- Perform the following to confirm the secondary air injection system pending codes: Press ENTER (Exit).

- Check for pending DTCs.

OK:

No pending DTC is output.

- After "Air injection check" is completed, check for All Readiness by entering the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

- Input the DTC: P2440, P2441, P2442 or P2443.

- Check the DTC judgment result.





HINT
- 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 is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.

HINT
- If no permanent DTC is output, the system is normal.
- If a permanent DTC is output, the system is malfunctioning.
- Turn the engine switch off.

WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
Refer to "Data List / Active Test" [Air Pump Pressure (Absolute), Air Pump2 Pressure (Absolute) and Air Pump Pulsation Pressure] Data List / Active Test.

HINT
Determination by ECM monitoring:

The ECM locates malfunctions in the secondary air injection system by detecting the pressure in the secondary air injection passage between the air pump and air switching valve and stores a DTC. Soon after a cold engine start, the monitor runs for a short time while the secondary air injection system is both ON and OFF. The ECM detects both the pressure and the exhaust pulsation and compares them.

The following 8 patterns are secondary air injection system pressure conditions in the secondary air injection system passage.

Pressure Condition in Secondary Air Injection System Case 1





Pressure Condition in Secondary Air Injection System Case 2





Pressure Condition in Secondary Air Injection System Case 3





Pressure Condition in Secondary Air Injection System Case 4





Pressure Condition in Secondary Air Injection System Case 5





Pressure Condition in Secondary Air Injection System Case 6





Pressure Condition in Secondary Air Injection System Case 7





Pressure Condition in Secondary Air Injection System Case 8





If the detected pressure is high, the air pump is assumed to be ON and if it alternates sharply, the air switching valve is assumed to be open. The ECM locates malfunctions from the combination of pressures detected when the secondary air injection system is ON and OFF.

HINT
The exhaust pulsation value is calculated in the ECM. If the calculated value exceeds a certain level, the ECM determines that the exhaust pulsation is in the secondary air injection system.

HINT
- In case 3 and 7, as the pressure sensor detects a slight pump operation pulsation, the detected value is not constant. Since the pump outlet is blocked by closing the air switching valve, the average pressure is higher than in case 1 (approximately 12 to 20 kPa).
- In case 1, the average pressure is approximately 3 to 11 kPa. The value of 1 kPa indicated in the table above is a threshold for detecting pump malfunctions.






HINT
- By using the Techstream to perform the Air Injection Check operation in the System Check, the air-fuel ratio and the pressure in the secondary air injection system passage can be checked while the secondary air injection system is operating. This helps technicians to troubleshoot the system when it malfunctions. Furthermore, pending codes also can be checked by performing Utility / Air Injection Check / Automatic Mode after the repair.
- Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. 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.
- System Check:

- The pressure in the secondary air passage can be checked using the Techstream.

- Start the engine and warm it up.

- Turn the engine switch off.

- Connect the Techstream to the DLC3.

- Turn the engine switch on (IG).

- Turn the Techstream on.

- Enter the following menus: Powertrain / Engine and ECT / Utility / Air Injection Check / Manual Mode / AIR PUMP: ON, ASV 1: OPEN, ASV 2: OPEN and AIR PUMP: OFF, ASV 1: CLOSE, ASV 2: CLOSE.

HINT
When Manual Mode is selected, the Techstream initialization (atmospheric pressure measurement) is performed automatically. The initialization takes 10 seconds. After the initialization, AIR PUMP and ASV operation can be selected.

- Start the engine.

- Perform the secondary air injection system forced operation while the engine is idling.

- Check that the air pump (AIR PUMP), air switching valve (ASV) and pressure in the secondary air injection system passage (PRESSURE) displayed on the Techstream indicate the conditions shown in the table below.

Standard:





- *1: Average pumping pressure (gauge pressure). The pressure should be 1 kPa or higher when the secondary air injection system operates.

- *2: The cumulative exhaust pulsation calculated by the ECM. If the calculated value exceeds a certain level, the ECM determines that the exhaust pulsation is in the secondary air injection system.

- Turn the engine switch off.

NOTICE:
- This Air Injection Check only allows technicians to operate the secondary air injection system for a maximum of 5 seconds. Furthermore, the check can only be performed up to 4 times per trip. If the test is repeated, intervals of at least 30 seconds are required between checks. While secondary air injection system operation using the Techstream is prohibited, the Techstream display indicates the prohibition (WAIT or ERROR). If ERROR is displayed on the Techstream during the test, stop the engine for 10 minutes, and then try again.
- Performing Air Injection Check repeatedly may cause damage to the secondary air injection system. If it is necessary to repeat the check, leave an interval of several minutes between System Check operations to prevent the system from overheating.
- When performing the Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the engine switch turned on (IG) or the engine running.
- Turn the engine switch off when the Air Injection Check operation finishes.
HINT
- 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.
PROCEDURE

1. CHECK FOR ANY OTHER DTCS OUTPUT (IN ADDITION TO SECONDARY AIR INJECTION SYSTEM DTCS)

(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 and ECT / Trouble Codes.

(e) Read DTCs and freeze frame data.

Result





HINT
If any DTCs other than P0412, P0416, P0417, P2440, P2441, P2442 and/or P2443 are output, troubleshoot those DTCs first.

D -- GO TO DTC CHART SFI System

C -- GO TO AIR SWITCHING VALVE INSPECTION PROCEDURE (P0416 AND P0417)

B -- GO TO AIR SWITCHING VALVE INSPECTION PROCEDURE (P0412)
A -- Continue to next step.

2. PERFORM ACTIVE TEST USING TECHSTREAM (SECONDARY AIR INJECTION SYSTEM OPERATION)





(a) Perform a visual check:

(1) Start the engine and warm it up.

(2) Turn the engine switch off.

(3) Disconnect the No. 1 and No. 2 air injection system hoses.

(4) Connect the Techstream to the DLC3.

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

(6) Turn the Techstream on.

(7) Enter the following menus: Powertrain / Engine and ECT / Utility / Air Injection Check / Manual Mode / AIR PUMP: ON, ASV1: OPEN, ASV2: OPEN.

HINT
When Manual Mode is selected, the Techstream initialization (atmospheric pressure measurement) is performed automatically. The initialization takes 10 seconds. After the initialization, AIR PUMP and ASV operation can be selected.

(8) Start the engine.

(9) Perform the secondary air injection system forced operation while the engine is idling.

(10) Place your hand near the air switching valve port and check that the exhaust gas pressure pulsates when the air switching valve is turned on.

CAUTION:
To avoid the danger of being burned by the exhaust gas, bring your hand close to the valve port slowly.

(11) Enter the following menus: Powertrain / Engine and ECT / Utility / Air Injection Check / Manual Mode / AIR PUMP: ON, ASV1: OPEN, ASV2: OPEN and AIR PUMP: ON, ASV1: CLOSE, ASV2: CLOSE.

(12) Check that the exhaust gas does not pulsate when the ASV is turned off.

(13) Turn the engine switch off.

NOTICE:
- This Air Injection Check only allows technicians to operate the secondary air injection system for a maximum of 5 seconds. Furthermore, the check can only be performed up to 4 times per trip. If the test is repeated, intervals of at least 30 seconds are required between checks. While secondary air injection system operation using the Techstream is prohibited, the Techstream display indicates the prohibition (WAIT or ERROR). If ERROR is displayed on the Techstream during the test, stop the engine for 10 minutes, and then try again.
- Performing Air Injection Check repeatedly may cause damage to the secondary air injection system. If it is necessary to repeat the check, leave an interval of several minutes between System Check operations to prevent the system from overheating.
- When performing the Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the engine switch turned on (IG) or the engine running.
- Turn the engine switch off when the Air Injection Check operation finishes.

OK:





Text in Illustration





NG -- INSPECT AIR TUBE (BLOCKAGE AND LEAK)
OK -- Continue to next step.

3. INSPECT AIR SWITCHING VALVE ASSEMBLY (PRESSURE SENSOR)

(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 and ECT / Data List / Air pump pressure (Absolute) and Air Pump2 Pressure (Absolute).

(e) Check the pressure displayed on the Techstream.

Standard pressure:

45 to 135 kPa

HINT
The Techstream displays the air pump pressure as absolute pressure.

Result





C -- REPLACE AIR SWITCHING VALVE ASSEMBLY Removal

B -- REPLACE AIR SWITCHING VALVE ASSEMBLY Removal

A -- END

4. INSPECT AIR TUBE (BLOCKAGE AND LEAK)





(a) Check that the No. 3 and No. 4 air tubes are securely connected to both the exhaust manifold and the air switching valve.

(b) Inspect the air tube for blockages and damage.

OK:

No blockages in or damage to air tubes.

Text in Illustration





NG -- REPLACE AIR TUBE
OK -- Continue to next step.

5. INSPECT AIR SWITCHING VALVE ASSEMBLY

(a) Inspect the air switching valve assembly for bank 1 Air Switching Valve (for Bank 1).

(b) Inspect the air switching valve assembly for bank 2 Air Switching Valve (for Bank 2).

Result





C -- REPLACE AIR SWITCHING VALVE ASSEMBLY Removal

B -- REPLACE AIR SWITCHING VALVE ASSEMBLY Removal
A -- Continue to next step.

6. INSPECT AIR INJECTION VSV RELAY (AI-VSV)

(a) Inspect the air injection VSV relay (AI-VSV) Testing and Inspection.

NG -- REPLACE AIR INJECTION VSV RELAY (AI-VSV)
OK -- Continue to next step.

7. CHECK AIR INJECTION VSV RELAY (AI-VSV) (POWER SOURCE)





(a) Remove the air injection VSV relay (AI-VSV).

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





Text in Illustration





(c) Reinstall the air injection VSV relay (AI-VSV).

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

8. CHECK HARNESS AND CONNECTOR (AIR INJECTION VSV RELAY (AI-VSV) - ECM)

(a) Remove the air injection VSV relay (AI-VSV).

(b) Disconnect the ECM connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):





Standard Resistance (Check for Short):





(d) Reinstall the air injection VSV relay (AI-VSV).

(e) Reconnect the ECM connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

9. INSPECT AIR INJECTION CONTROL DRIVER (POWER SOURCE OF AIR INJECTION CONTROL DRIVER)





(a) Disconnect the air injection control driver connectors.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





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

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

10. CHECK HARNESS AND CONNECTOR (ECM - AIR INJECTION CONTROL DRIVER)

(a) Disconnect the ECM connectors.

(b) Disconnect the air injection control driver connectors.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

11. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Disconnect the air injection control driver connector.





(b) Connect terminals DI and SIV of the wire harness connector for the air injection control driver.

Text in Illustration





(c) Connect the Techstream to the DLC3.

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

(e) Enter the following menus: Powertrain / Engine and ECT / Utility / Air Injection Check / Manual Mode / AIR PUMP: ON, ASV 1: OPEN, ASV 2: OPEN.

HINT
When Manual Mode is selected, the Techstream initialization (atmospheric pressure measurement) is performed automatically. The initialization takes 10 seconds. After the initialization, AIR PUMP and ASV operation can be selected.

(f) Start the engine.

(g) Perform the secondary air injection system forced operation while the engine is idling.

(h) Measure the voltage between the SIV and E terminals of the ECM connector when the secondary air injection system is ON and OFF.

(i) Turn the engine switch off.

NOTICE:
- Performing Air Injection Check repeatedly may cause damage to the secondary air injection system. If it is necessary to repeat the check, leave an interval of several minutes between System Check operations to prevent the system from overheating.
- When performing the Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the engine switch turned on (IG) or the engine running.
- Turn the engine switch off when the Air Injection Check operation finishes.

Standard Voltage:









(j) Connect terminals DI and SIP of the wire harness connector for the air injection control driver.

Text in Illustration





(k) Connect the Techstream to the DLC3.

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

(m) Enter the following menus: Powertrain / Engine and ECT / Utility / Air Injection Check / Manual Mode / AIR PUMP: ON, ASV 1: OPEN, ASV 2: OPEN.

HINT
When Manual Mode is selected, the Techstream initialization (atmospheric pressure measurement) is performed automatically. The initialization takes 10 seconds. After the initialization, AIR PUMP and ASV operation can be selected.

(n) Start the engine.

(o) Perform the secondary air injection system forced operation while the engine is idling.

(p) Measure the voltage between the SIP and E terminals of the ECM connector when the secondary air injection system is ON and OFF.

(q) Turn the engine switch off.

NOTICE:
- Performing Air Injection Check repeatedly may cause damage to the secondary air injection system. If it is necessary to repeat the check, leave an interval of several minutes between System Check operations to prevent the system from overheating.
- When performing the Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the engine switch turned on (IG) or the engine running.
- Turn the engine switch off when the Air Injection Check operation finishes.

Standard Voltage:





(r) Reconnect the air injection control driver connector.

NG -- REPLACE ECM Removal
OK -- Continue to next step.

12. REPLACE AIR INJECTION CONTROL DRIVER

(a) Replace the air injection control driver Removal.

NEXT -- Continue to next step.

13. CHECK WHETHER DTC OUTPUT RECURS (DTC P2440, P2441, P2442 AND/OR P2443)

(a) Start the engine and warm it up.

(b) Turn the engine switch off.

(c) Connect the Techstream to the DLC3.

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

(e) Turn the Techstream on.

(f) Clear DTCs (if stored) DTC Check / Clear.

(g) Enter the following menus: Powertrain / Engine and ECT / Utility / Air Injection Check / Automatic Mode.

(h) Start the engine after the Techstream initialization is finished.

(i) Perform the System Check operation by pressing ENTER (Next).

(j) Perform the following to confirm the secondary air injection system pending codes: Press the Exit button.

(k) Check pending DTCs.

(l) Turn the engine switch off.

OK:

No pending DTC output.

NOTICE:
- When performing the Air Injection Check operation after the battery cable has been reconnected, wait for 7 minutes with the engine switch turned on (IG) or the engine running.
- Turn the engine switch off when the Air Injection Check operation finishes.
NG -- REPLACE ECM Removal

OK -- END