DTC P2432: Secondary Air System Air Flow/Pressure Sensor Circuit Low Bank 1: Notes

DTC detecting condition: 

Immediately at fault recognition

Wiring diagram: 

Engine Electrical System Ref. to WIRING SYSTEM>Engine Electrical System>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK CURRENT DATA  .
   1. Turn the ignition switch to ON.
   2. Read the value of «Sec. Air Piping Pressure» using Subaru Select Monitor.
      NOTE: For detailed operation procedures, refer to "Read Current Data For Engine". Ref. to ENGINE (DIAGNOSTICS) (STI)>Subaru Select Monitor .

   Is the value of «Sec. Air Piping Pressure» less than 53.3 kPa (400 mmHg, 15.8 inHg)?

   Yes:  Go to  2

   No:  Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

   NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2. CHECK POWER SUPPLY OF SECONDARY AIR COMBINATION VALVE  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the connector from the secondary air combination valve LH.
   3. Turn the ignition switch to ON.
   4. Measure the voltage between the secondary air combination valve LH connector and chassis ground.

      Connector & terminal 

      (E40) No. 1 (+) - Chassis ground (-):

   Is the voltage 4.5 V or more?

   Yes:  Go to  3

   No:  Repair the harness and connector.

   NOTE: In this case, repair the following item:

   • Open circuit in harness between ECM connector and secondary air combination valve LH connector
   • Poor contact of ECM connector
   • Poor contact of coupling connector
3. CHECK HARNESS BETWEEN ECM AND SECONDARY AIR COMBINATION VALVE CONNECTOR  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the connector from ECM.
   3. Measure the resistance of harness between ECM connector and secondary air combination valve LH connector.

      Connector & terminal 

      (B137) No. 9 - (E40) No. 2:

   Is the resistance less than 1 Ω?

   Yes:  Go to  4

   No:  Repair the harness and connector.

   NOTE: In this case, repair the following item:

   • Open circuit in harness between ECM connector and secondary air combination valve LH connector
   • Poor contact of coupling connector
4. CHECK HARNESS BETWEEN ECM AND SECONDARY AIR COMBINATION VALVE CONNECTOR  .

   Measure the resistance between ECM connector and chassis ground.

   Connector & terminal 

   (B137) No. 9 - Chassis ground:

   Is the resistance 1 MΩ or more?

   Yes:  Go to  5

   No:  Repair the ground short circuit in harness between ECM connector and secondary air combination valve LH connector.

5. CHECK FOR POOR CONTACT  .

   Check for poor contact of the ECM and secondary air combination valve LH connector.

   Is there poor contact of the ECM or secondary air combination valve LH connector?

   Yes:  Repair the poor contact of the ECM or secondary air combination valve LH connector.

   No:  Replace the secondary air combination valve LH. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (STI)>Secondary Air Combination Valve .