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DTC P2258: Secondary Air System Control "A" Circuit HIGH: Notes

DTC detecting condition:

Immediately at fault recognition

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode Refer to ENGINE (DIAGNOSTICS) (STI)>CLEAR MEMORY MODE>OPERATION , and inspection mode Refer to ENGINE (DIAGNOSTICS) (STI)>INSPECTION MODE>PROCEDURE .

Wiring diagram:

Engine Electrical System Refer to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM>WIRING DIAGRAM .

G12456928

Courtesy of SUBARU OF AMERICA, INC.

CHECK HARNESS BETWEEN ECM AND SECONDARY AIR PUMP RELAY CONNECTOR.
1. Turn the ignition switch to OFF.
2. Disconnect the connector from ECM.
3. Remove the secondary air pump relay.
4. Measure the voltage between ECM connector and chassis ground.
Connector & terminal

(B135) No. 27 (+) - Chassis ground (-):

Is the voltage 10 V or more?

Yes: Repair the short circuit to power in harness between ECM connector and secondary air pump relay connector.

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.