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

1. -

DTC detecting condition:

Immediately at fault recognition

Wiring diagram:

Engine Electrical System Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

G13626787

Courtesy of SUBARU OF AMERICA, INC.

CAUTION:

Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .

NOTE:

After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO)>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .

CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR (SHORT TO POWER SUPPLY) .
1. Turn the ignition switch to OFF.
2. Measure the voltage between ECM connector and engine ground.
  Connector and terminal
  
  (E53) No. 88 (+) - Engine 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 (OPEN CIRCUIT) .
1. Disconnect the connector from ECM.
2. Measure the resistance between the ECM connector and engine ground.
  Connector and terminal
  
  (B62) No. 69 - Engine ground:
  
  (B62) No. 70 - Engine ground:
  
  (B62) No. 71 - Engine ground:
  
  (B62) No. 72 - Engine ground:
  
  Is the resistance less than 5 Ω?
  
  Yes : Repair the poor contact of ECM connector.
  
  No : Repair the following item.
  - Open circuit of harness between ECM connector and engine ground
  - Poor contact of coupling connector