P2433
3UR-FE ENGINE CONTROL: SFI SYSTEM: P2431-P2433,P2436-P2438: Secondary Air Injection System Air Flow / Pressure Sensor Circuit Range / Performance Bank1
P2438 - Secondary Air Injection System Air Flow / Pressure Sensor Circuit High Bank 2
DESCRIPTION
The Secondary Air injection (AIR) system consists of an air pump, the Air Switching Valve (ASV), a pressure sensor, the Air Injection Control Driver (AID) and the ECM. For a short time after a cold engine start, the AIR system pumps secondary air to the exhaust port of the cylinder head to purify the exhaust emissions. The secondary air is supplied by the air pump and is pumped to the exhaust port through the ASV.
The AID drives the ASV and the air pump according to command signals transmitted by the ECM. The pressure sensor detects the pressure in the secondary air passage when the AIR system is ON and OFF, and transmits a pressure signal to the ECM.
The AID is not only equipped to drive the pump and valve, but also with a diagnosis function to detect malfunctions in the AIR system circuit.
HINT
As a large current is required to drive the air pump and ASV, an AID is installed to this system.
MONITOR DESCRIPTION
The ECM monitors the pressure in the secondary air passage using the pressure sensor located on the air switching valve in the secondary air injection system.
If there is a defect in the sensor or the sensor circuit, the voltage level deviates from the normal operating range, the ECM interprets this deviation as a malfunction in the pressure sensor or circuit and stores DTC(s).
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
P2432, P2433, P2437 and P2438
P2431 and P2436:
TYPICAL MALFUNCTION THRESHOLDS
P2432 and P2437:
P2433 and P2438:
P2431 and P2436:
COMPONENT OPERATING RANGE
CONFIRMATION DRIVING PATTERN
NOTICE:
- 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 Techstream is prohibited, the Techstream display indicates the prohibition (WAIT or ERROR).
If an ERROR is displayed on the Techstream 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 to on (IG) or the engine running.
- Turn the engine switch off when the Secondary Air Injection Check operation finishes.
1. Start the engine and warm it up.
2. Turn the engine switch off.
3. Connect the Techstream to the DLC3.
4. Turn the engine switch on (IG).
5. Turn the Techstream on.
6. Clear the DTCs (if set) DTC Check / Clear.
7. Turn the engine switch off and wait for at least 30 seconds.
8. Turn the engine switch on (IG) and turn the Techstream on [A].
9. Enter the following menus: Powertrain / Engine and ECT / Utility / Secondary Air Injection Check / Automatic Mode.
10. Start the engine after the Techstream initialization is finished.
11. Perform the System Check operation by pressing ENTER (Next).
12. After operating the AIR system, perform the following to confirm the AIR system pending codes: Press the ENTER (Exit).
13. Check pending DTCs [B].
OK:
No pending DTC is output.
14. After the "Secondary Air Injection Check" is completed, check for All Readiness by entering the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
15. Input the DTC: P2431, P2432, P2433, P2436, P2437 or P2438.
16. 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.
17. If the test 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.
18. Turn the engine switch off.
WIRING DIAGRAM
Refer to DTC P0412 P0412.
INSPECTION PROCEDURE
HINT
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.
PROCEDURE
1. CHECK HARNESS AND CONNECTOR (PRESSURE SENSOR - ECM)
(a) Disconnect the C35 or C36 pressure sensor connector.
(b) Disconnect the A38 and C53 ECM 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.
2. INSPECT AIR SWITCHING VALVE (PRESSURE SENSOR)
(a) Connect a pressure gauge to the air pressure sensor as shown in the illustration.
(b) Connect the Techstream to the DLC3.
(c) Turn the engine switch on (IG) and 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 that the pressure displayed on the Techstream fluctuates when applying the pressure to the pressure sensor with the pressure gauge.
NOTICE:
Do not let foreign matter enter the sensor when applying pressure.
OK:
Pressure fluctuates in response to pressure applied with pressure gauge.
HINT
The Techstream displays the air pump pressure as absolute pressure.
NG -- REPLACE AIR SWITCHING VALVE Removal
OK -- REPLACE ECM Removal