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DTC P0032: A/F/O2 Heater Control Circuit High Bank 1 Sensor 1: Notes

DTC detecting condition:

Immediately at fault recognition

CAUTION: After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to ENGINE (DIAGNOSTICS) (STI)>Clear Memory Mode>OPERATION , and inspection mode Ref. to ENGINE (DIAGNOSTICS) (STI)>Inspection Mode>PROCEDURE .

Wiring diagram:

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

G12456917

Courtesy of SUBARU OF AMERICA, INC.

CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR .
1. Turn the ignition switch to OFF.
2. Measure the voltage between ECM connector and chassis ground.
  Connector & terminal
  
  (B136) No. 5 (+) - Chassis ground (-):
  
  (B136) No. 6 (+) - Chassis ground (-):
Is the voltage 10 V or more?

Yes: Repair the short circuit to power in the harness between ECM connector and front oxygen (A/F) sensor connector.

No: Go to 2
CHECK GROUND CIRCUIT FOR ECM .
1. Disconnect the connector from ECM.
2. Measure the resistance between ECM connector and chassis ground.
  Connector & terminal
  
  (B134) No. 3 - Chassis ground:
  
  (B134) No. 4 - Chassis ground:
  
  (B134) No. 6 - Chassis ground:
  
  (B137) No. 1 - Chassis ground:
  
  (B137) No. 3 - Chassis ground:
Is the resistance less than 5 Ω?

Yes: Repair the poor contact of ECM connector.

No: Repair the harness and connector.
NOTE:
In this case, repair the following item:
- Open circuit of harness between ECM connector and engine ground
- Poor contact of coupling connector