P2431

2UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P2431: Secondary Air Injection System Air Flow / Pressure Sensor Circuit Range / Performance Bank1

DTC P2431 - Secondary Air Injection System Air Flow / Pressure Sensor Circuit Range / Performance Bank1

DTC P2432 - Secondary Air Injection System Air Flow / Pressure Sensor Circuit Low Bank1

DTC P2433 - Secondary Air Injection System Air Flow / Pressure Sensor Circuit High Bank1

DTC P2436 - Secondary Air Injection System Air Flow / Pressure Sensor Circuit Range / Performance Bank 2

DTC P2437 - Secondary Air Injection System Air Flow / Pressure Sensor Circuit Low Bank 2

DTC 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 cold engine starts, 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 sets a DTC.

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





WIRING DIAGRAM









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 D58 or D59 pressure sensor connector.
(b) Disconnect the A24 and D74 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 ignition switch to ON 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.
OK:
Pressure fluctuates in response to pressure applied with pressure gauge.

Result





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

C -- REPLACE AIR SWITCHING VALVE
B -- REPLACE AIR SWITCHING VALVE
A -- REPLACE ECM