P1440

2UZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P1440: Secondary Air Injection Vacuum Switching Valve Circuit Malfunction Bank 1

DTC P1440 - Secondary Air Injection Vacuum Switching Valve Circuit Malfunction Bank 1

DTC P1443 - Secondary Air Injection Vacuum Switching Valve Circuit Malfunction Bank 2

DESCRIPTION

The Secondary Air Injection (AIR) system pumps air to the exhaust port to accelerate the activation of the catalyst. The secondary air injection system consists of the ECM, air pump, Air Switching Valve (ASV) (EASV), Air Switching Valve No. 2 (ASV No. 2) (ASV1, 2), pressure sensor and Air Injection Control Driver (AID). The Air Switching Valve (ASV) (EASV) is an electromagnetic type and Air Switching Valve No. 2 (ASV No. 2) (ASV1, 2) is a vacuum type.
The secondary air injection system pumps pressurized air to the exhaust port by the air pump through the ASV and ASV No. 2. The ASV assists the ASV No. 2. The ASV No. 2 also controls air supply.
The ECM sends signals to the AID, and then the AID operates the air pump and ASV. The pressure sensor detects pressure and exhaust pulsation in the system when the system operates and when it does not operate, and sends the data to the ECM.










MONITOR DESCRIPTION

The ECM detects an open or short in the circuit of the VSV for air injection system according to the AIV1 (AIV2) terminal voltage, stores the DTC, and then illuminates the MIL. When the AIV1 (AIV2) terminal voltage is less than half of the +B voltage while the VSV for air injection system is not operating, the ECM determines it as a malfunction.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

All:





P1440:





P1443:





TYPICAL MALFUNCTION THRESHOLDS

P1440:





P1443:





WIRING DIAGRAM





INSPECTION PROCEDURE
HINT: 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 be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE

1. CHECK POWER SOURCE CIRCUIT (AIR INJECTION SYSTEM)




(a) Disconnect the V10 or V11 VSV for air injection system control connector.
(b) Turn the ignition switch ON.
(c) Measure the voltage between terminal 1 of the VSV connector and body ground.
Standard voltage:
9 V or more
(d) Reconnect the VSV for air injection system control connector.
NG -- REPAIR OR REPLACE POWER SOURCE CIRCUIT (AIR INJECTION SYSTEM)
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (ECM - VSV FOR AIR INJECTION CONTROL SYSTEM)




(a) Disconnect the E5 ECM connector.
(b) Disconnect the VSV for air injection control connector.
(c) Measure the resistance between the VSV connector and ECM.
Standard resistance:





(d) Measure the resistance between the VSV connector and body ground.
Standard resistance:





(e) Reconnect the ECM connector.
(f) Reconnect the VSV for air injection control connectors.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK VSV (RESISTANCE)




(a) Disconnect the V10 or V11 VSV for air injection system connector.
(b) Disconnect the 2 vacuum hoses from the VSV.
(c) Measure the resistance of the VSV terminals.
Standard resistance:





(d) Reconnect the VSV for air injection system connector.
(e) Reconnect the vacuum hose.
NG -- REPLACE VSV
OK -- REPLACE ECM