SFI SYSTEM(w/ Secondary Air Injection System), Diagnostic DTC:P2440, P2441, P2442, P2443

DTC Code	DTC Name
P2440	Secondary Air Injection System Switching Valve Stuck Open Bank1
P2441	Secondary Air Injection System Switching Valve Stuck Close Bank1
P2442	Secondary Air Injection System Switching Valve Stuck Open Bank 2
P2443	Secondary Air Injection System Switching Valve Stuck Closed Bank 2

DESCRIPTION

Refer to DTC P0412 Click here.

DTC No.	DTC Detection Condition	Trouble Area
P2440 P2442	The pressure sensor detects pulsation of the exhaust gas despite the ECM commanding the Air Switching Valve (ASV) to close, while the engine is running (1 trip detection logic).	ASV Open or short in ASV circuit Pressure sensor Pressure sensor circuit Air Injection Control Driver (AID) ECM
P2441 P2443	The pressure sensor detects no pulsation of the exhaust gas despite the ECM commanding the Air Switching Valve (ASV) to open, while the engine is running (2 trip detection logic).	ASV Open or short in ASV circuit Vacuum hose (ASV - pressure sensor) Air injection hose Pressure sensor Pressure sensor circuit Air Injection Control Driver (AID) ECM

DTC No.

DTC Detection Condition

Trouble Area

P2440

P2442

The pressure sensor detects pulsation of the exhaust gas despite the ECM commanding the Air Switching Valve (ASV) to close, while the engine is running (1 trip detection logic).

ASV
Open or short in ASV circuit
Pressure sensor
Pressure sensor circuit
Air Injection Control Driver (AID)
ECM

P2441

P2443

The pressure sensor detects no pulsation of the exhaust gas despite the ECM commanding the Air Switching Valve (ASV) to open, while the engine is running (2 trip detection logic).

ASV
Open or short in ASV circuit
Vacuum hose (ASV - pressure sensor)
Air injection hose
Pressure sensor
Pressure sensor circuit
Air Injection Control Driver (AID)
ECM

Tech Tips

Air switching valve normal operation:

When the Air Switching Valve (ASV) is open, exhaust gas pulsation occurs in the secondary air passage.

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

MONITOR DESCRIPTION

The ECM monitors the pressure in the secondary air passage using the pressure sensor connected to the ASV of the Secondary Air Injection (AIR) system.

If either of the following conditions occurs, the ECM interprets it as a malfunction of the AIR system, illuminates the MIL and stores DTC(s):

Exhaust gas pulsation is detected by the pressure sensor despite the ECM commanding the ASV to close.
Exhaust gas pulsation is not detected by the pressure sensor despite the ECM commanding the ASV to open.

WIRING DIAGRAM

Refer to DTC P0412 Click here.

CAUTION / NOTICE / HINT

Tech Tips

Determination by ECM monitoring:

The ECM locates malfunctions in the Secondary Air Injection (AIR) system by detecting the pressure in the AIR passage between the air pump and Air Switching Valve (ASV) and stores DTC(s). Soon after a cold engine start, the monitor runs for a short time while the AIR system is both ON and OFF. The ECM detects both the pressure and the exhaust pulsation and compares them.

The following 8 patterns are AIR system pressure conditions in the AIR system passage.

Pressure Condition in Secondary Air Injection System Case 1:
Air Pump	ON
Air Switching Valve	Open
Pressure	2.4 kPa or higher
Pulsation Detection	Exhaust gas pulsation detected

Pressure Condition in Secondary Air Injection System Case 2:
Air Pump	OFF
Air Switching Valve	Open
Pressure	Below 2.4 kPa
Pulsation Detection	Exhaust gas pulsation detected

Pressure Condition in Secondary Air Injection System Case 3:
Air Pump	ON
Air Switching Valve	Closed
Pressure	2.4 kPa or higher
Pulsation Detection	Exhaust gas pulsation not detected

Pressure Condition in Secondary Air Injection System Case 4:
Air Pump	OFF
Air Switching Valve	Close
Pressure	Below 2.4 kPa
Pulsation Detection	Exhaust gas pulsation not detected

Pressure Condition in Secondary Air Injection System Case 5:
Air Pump	ON
Air Switching Valve	Open
Pressure	2.4 kPa or higher
Pulsation Detection	Exhaust gas pulsation detected

Pressure Condition in Secondary Air Injection System Case 6:
Air Pump	OFF
Air Switching Valve	Open
Pressure	Below 2.4 kPa
Pulsation Detection	Exhaust gas pulsation detected

Pressure Condition in Secondary Air Injection System Case 7:
Air Pump	ON
Air Switching Valve	Closed
Pressure	2.4 kPa or higher
Pulsation Detection	Exhaust gas pulsation not detected

Pressure Condition in Secondary Air Injection System Case 8:
Air Pump	OFF
Air Switching Valve	Close
Pressure	Below 2.4 kPa
Pulsation Detection	Exhaust gas pulsation not detected

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

Tech Tips

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 AIR system.

Tech Tips

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 ASV, the average pressure is higher than in case 1 (approximately 20 to 30 kPa).
In case 1, the average pressure is approximately 3 to 11 kPa. The value of 2.4 kPa indicated in the table above is a threshold for detecting pump malfunctions.

Detected Conditions while AIR Operating: Air Pump ON, ASV Open	Detected Conditions while AIR not Operating: Air Pump OFF, ASV Closed	ECM Determination	DTCs Output
Case 1	Case 8	Normal	-
Case 1	Case 6	ASV stuck open	P2440 or P2442
Case 1	Case 7	Air pump stuck ON	P2444 or P2446
Case 2	Case 8	Air pump stuck OFF	P2445 or P2447
Case 3	Case 8	ASV stuck closed	P2441 or P2443
Case 1	Case 5	ASV stuck open and air pump stuck ON	P2440 and P2444 or P2442 and P2446
Case 2	Case 6	ASV stuck open and air pump stuck OFF	P2440 and P2445 or P2442 and P2447
Case 3	Case 7	ASV stuck closed and air pump stuck ON	P2441 and P2444 or P2443 and P2446
Case 4	Case 8	ASV stuck closed and air pump stuck OFF	P2441 and P2445 or P2443 and P2447

Tech Tips

If the vacuum hose between the ASV and the pressure sensor is not connected correctly, case 4 may occur.
By using the GTS to perform the Secondary 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 / Secondary Air Injection Check / Automatic Mode after the repair.
Read freeze frame data using the GTS. 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 GTS.

Start the engine and warm it up.
Turn the engine switch off.
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Manual Mode / AIR PUMP 1: ON, ASV1: OPEN, AIR PUMP 2: ON, ASV2: OPEN and AIR PUMP 1: OFF, ASV1 CLOSE, AIR PUMP 2: OFF, ASV2 CLOSE.

Tech Tips

When Manual Mode is selected, the GTS 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 AIR system intrusive operation while the engine is idling.

Check that the status of the air pump (AIR PUMP), ASV and pressure in the AIR system passage (PRESSURE) displayed on the GTS indicate the conditions shown in the table below.

Standard

Operations	AIR PUMP	ASV	PRESSURE*1	PULSATION*2
AIR PUMP: ON, ASV: OPEN	ON	OPEN	2.4 kPa or higher	20 kPa or higher
AIR PUMP: OFF, ASV: CLOSE	OFF	CLOSE	Below 2.4 kPa	Below 30 kPa

*1:

Average pumping pressure (gauge pressure). The pressure should be 2.4 kPa or higher when the AIR 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 AIR system.

Turn the engine switch off.
Note
- This Secondary Air Injection Check only allows technicians to operate the AIR 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 AIR system operation using the GTS is prohibited, the GTS display indicates the prohibition (WAIT or ERROR).
  
  If an ERROR is displayed on the GTS during the test, stop the engine for 10 minutes, and then try again.
- Performing the Secondary Air Injection Check repeatedly may cause damage to the AIR system. If necessary, leave an interval of several minutes between System Check operations to prevent the system from overheating.
- When performing the Secondary 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 Secondary Air Injection Check operation finishes.

Tech Tips

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

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

Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

Read DTCs.

Result
Result	Proceed to
P2440, P2441, P2442 and/or P2443 are output	A
P2440, P2441, P2442 and/or P2443 and P0412 and/or P0415 are output	B
P2440, P2441, P2442 and/or P2443 and other DTCs (except P0412 and P0415) are output	C

If any DTCs other than P0412, P0415, P2440, P2441, P2442 and/or P2443 are output, troubleshoot those DTCs first.

GO TO AIR SWITCHING VALVE INSPECTION PROCEDURE (P0412 AND P0415) Click here

GO TO DTC CHART Click here

INSPECT AIR PUMP ASSEMBLY
1. Inspect the air pump assembly.
  
  Click here
NG
REPLACE AIR PUMP ASSEMBLY Click here

OK

PERFORM ACTIVE TEST USING GTS


*1	for Bank 1:
*2	for Bank 2:

Visual check

Start the engine and warm it up.
Turn the engine switch off.
Disconnect the No. 1 air hose.
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Manual Mode / AIR PUMP 1: ON, ASV1: OPEN, AIR PUMP 2: ON, ASV2: OPEN.

Tech Tips

When Manual Mode is selected, the GTS initialization (atmospheric pressure measurement) is performed automatically. The initialization takes 10 seconds. After the initialization, AP and ASV operation can be selected.
Start the engine.
Perform the AIR system intrusive operation while the engine is idling.
Place your hand near the air switching valve port and check that the exhaust gas pressure pulsates when the ASV is turned on.

CAUTION:

To avoid the danger of being burned by the exhaust gas, bring your hand close to the valve port slowly.
Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Manual Mode / AIR PUMP 1: ON, ASV1: OPEN, AIR PUMP 2: ON, ASV2: OPEN and AIR PUMP 1: ON, ASV1: CLOSE, AIR PUMP 2: ON, ASV2: CLOSE.
Check that the exhaust gas does not pulsate when the ASV is turned off.

Turn the engine switch off.

Note

This Secondary Air Injection Check only allows technicians to operate the AIR 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 AIR system operation using the GTS is prohibited, the GTS display indicates the prohibition (WAIT or ERROR).

If an ERROR is displayed on the GTS during the test, stop the engine for 10 minutes, and then try again.
Performing the Secondary Air Injection Check repeatedly may cause damage to the AIR system. If necessary, leave an interval of several minutes between System Check operations to prevent the system from overheating.
When performing the Secondary 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 Secondary Air Injection Check operation finishes.

Air Pump Operations	ASV Operations	Exhaust Gas Pulsation
ON	OFF	Not detected
ON	ON	Detected

Other inspection method:

The ASV operation can be confirmed by checking the cumulative pressure pulsation* provided in the System Check.

Perform System Check operation under Manual Mode.

*: 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 AIR system.

Start the engine and warm it up.
Turn the engine switch off.
Connect the GTS to the DLC3.
Turn the engine switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Manual Mode / AIR PUMP 1: ON, ASV1: OPEN, AIR PUMP 2: ON, ASV2: OPEN and AIR PUMP 1: OFF, ASV1: CLOSE, AIR PUMP 2: OFF, ASV2: CLOSE.
Start the engine after the GTS initialization is finished.
Perform the AIR system intrusive operation while the engine is idling.
Check that the air-fuel ratio and pressure in the secondary air injection system passage (Pulsation) displayed on the GTS indicate the conditions shown in the table below.
Turn the engine switch off.

AIR System Operation

Pulsation Condition

(ECM Calculation)

Air-Fuel Ratio

(Reference)

AIR PUMP: ON, ASV: OPEN

20 kPa or higher

18 or more

AIR PUMP: OFF, ASV: CLOSE

Below 30 kPa

Approximately 14.5

(around stoichiometric air-fuel ratio)

Reference:

If the air pump operation is confirmed as normal Click here, the air-fuel ratio detected in front of three-way catalytic converter changes in response to the secondary air pumped into the exhaust port when the air pump operates.

Result
Result	Proceed to
NG	A
OK	B

INSPECT VACUUM HOSES (AIR SWITCHING VALVE - PRESSURE SENSOR) Click here

INSPECT AIR TUBE (BLOCKAGES AND LEAKAGES)
1. Check that the No. 2 and No. 3 air tubes are securely connected to both the exhaust manifold and the ASV.
  
  *1 for Bank 1:
  
  *2 for Bank 2:
2. Inspect the air tube for blockages and damage.
  
  OK
  
  No blockages and damage on intake pipe.
NG
REPLACE AIR TUBE Click here

OK
INSPECT AIR SWITCHING VALVE ASSEMBLY
1. Inspect the air switching valve assembly Click here.
NG
REPLACE AIR SWITCHING VALVE ASSEMBLY Click here

OK

OK
No blockages and damage on intake pipe.

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

Disconnect the air injection control driver (AID) connectors.


*1	Front view of wire harness connector: (to AID for Bank 1)
*2	Front view of wire harness connector: (to AID for Bank 2)

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

Standard Resistance

Tester Connection	Condition	Specified Condition
C174-1 (E) - Body ground	Always	Below 1 Ω
C176-1 (E2) - Body ground	Always	Below 1 Ω

Turn the engine switch on (IG).

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

Standard Voltage

Tester Connection	Switch Condition	Specified Condition
C173-1 (BATT) - Body ground	Always	11 to 14 V (near battery voltage)
C174-5 (+B) - Body ground	Engine switch on (IG)	11 to 14 V (near battery voltage)
C175-1 (BAT2) - Body ground	Always	11 to 14 V (near battery voltage)
C176-5 (+B2) - Body ground	Engine switch on (IG)	11 to 14 V (near battery voltage)

REPAIR OR REPLACE AIR INJECTION CONTROL DRIVER POWER SOURCE CIRCUIT

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

Disconnect the ECM connector.
Disconnect the AID connector.

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

Standard Resistance

Tester Connection	Condition	Specified Condition
C45-61 (AIRV) - C174-3 (SIV)	Always	Below 1 Ω
C45-60 (ARV2) - C176-3 (SIV2)	Always	Below 1 Ω
C45-61 (AIRV) or C174-3 (SIV) - Body ground	Always	10 kΩ or higher
C45-60 (ARV2) or C176-3 (SIV2) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

PERFORM ACTIVE TEST USING GTS

Disconnect the AID connectors.


*1	AID (for Bank 1)
*2	AID (for Bank 2)
*3	Front view of wire harness connector: (to AID for Bank 1)
*4	Front view of wire harness connector: (to AID for Bank 2)

Connect terminals DI and SIV or DI2 and SIV2 of the wire harness connector for the AID.
Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Manual Mode / AIR PUMP 1: ON, ASV 1: OPEN or AIR PUMP 2: ON, ASV 2: OPEN.

Tech Tips

When Manual Mode is selected, the GTS 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 AIR system forced operation while the engine is idling.
Measure the voltage between the SIV and E or SIV2 and E2 terminals of the ECM connector when the AIR system is ON and OFF.

Turn the engine switch off.

Note

Performing Secondary 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 Secondary 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 Secondary Air Injection Check operation finishes.

Standard Voltage

Tester Connection	Condition	Specified Condition
C174-3 (SIV) - C174-1 (E)	AIR PUMP: ON, ASV: OPEN	0.5 to 2 V
C176-3 (SIV2) - C176-1 (E2)	AIR PUMP: ON, ASV: OPEN	0.5 to 2 V
C174-3 (SIV) - C174-1 (E)	AIR PUMP: OFF, ASV: CLOSE	11 to 14 V
C176-3 (SIV2) - C176-1 (E2)	AIR PUMP: OFF, ASV: CLOSE	11 to 14 V

Connect terminals DI and SIP or DI2 and SIP2 of the wire harness connector for the AID.


*1	AID (for Bank 1)
*2	AID (for Bank 2)
*3	Front view of wire harness connector: (to AID for Bank 1)
*4	Front view of wire harness connector: (to AID for Bank 2)

Connect the GTS to the DLC3.
Turn the engine switch on (IG).
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Manual Mode / AIR PUMP 1: ON, ASV 1: OPEN or AIR PUMP 2: ON, ASV 2: OPEN.

Tech Tips

When Manual Mode is selected, the GTS 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 AIR system forced operation while the engine is idling.
Measure the voltage between the SIP and E or SIP2 and E2 terminals of the ECM connector when the AIR system is ON and OFF.

Turn the engine switch off.

Note

Performing Secondary 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 Secondary 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 Secondary Air Injection Check operation finishes.

Standard Voltage

Tester Connection	Condition	Specified Condition
C174-4 (SIP) - C174-1 (E)	AIR PUMP: ON, ASV: OPEN	0.5 to 2 V
C176-4 (SIP2) - C176-1 (E2)	AIR PUMP: ON, ASV: OPEN	0.5 to 2 V
C174-4 (SIP) - C174-1 (E)	AIR PUMP: OFF, ASV: CLOSE	11 to 14 V
C176-4 (SIP2) - C176-1 (E2)	AIR PUMP: OFF, ASV: CLOSE	11 to 14 V

REPLACE ECM Click here

REPLACE AIR INJECTION CONTROL DRIVER (BANK 1 OR BANK 2)
1. Replace the air injection control driver (bank 1 or bank 2) Click here.
NEXT
CHECK WHETHER DTC OUTPUT RECURS (DTC P2440, P2441, P2442 AND/OR P2443)
1. Start the engine and warm it up.
2. Turn the engine switch off.
3. Connect the GTS to the DLC3.
4. Turn the engine switch on (IG) and turn the GTS on.
5. Clear DTCs (if output) Click here.
6. Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Automatic Mode.
7. Start the engine after the GTS initialization is finished.
8. Perform the System Check operation by pressing Next.
9. After operating the AIR system, perform the following to confirm the AIR system pending codes: Press the Exit button.
10. Refer to the confirmation driving pattern.
11. Check pending DTCs.
12. Turn the engine switch off.
  
  OK
  
  No pending DTC output.
  Note
  - When performing the Secondary 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 Secondary Air Injection Check operation finishes.
OK
END

NG
REPLACE ECM Click here
INSPECT VACUUM HOSES (AIR SWITCHING VALVE - PRESSURE SENSOR)
1. Check the vacuum hose connections with the pressure sensor and ASV.
2. Inspect the vacuum hose for blockages and damage.
  
  OK
  
  Vacuum hose has no blockages or damage.
NG
REPAIR OR REPLACE VACUUM HOSE

OK

INSPECT AIR SWITCHING VALVE ASSEMBLY (PRESSURE SENSOR)


*1	for Bank 1:
*2	Pressure Gauge
*3	for Bank 2:

Connect a pressure gauge to the air pressure sensor as shown in the illustration.
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Air pump pressure (Absolute) and Air Pump2 Pressure (Absolute).
Check that the pressure displayed on the tester fluctuates when applying the pressure to the pressure sensor with the pressure gauge.

OK

Pressure fluctuates in response to pressure applied with pressure gauge.

Tech Tips

The tester displays the air pump pressure as absolute pressure.

CHECK FOR INTERMITTENT PROBLEMS Click here

REPLACE AIR SWITCHING VALVE ASSEMBLY Click here