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Home >> Suzuki >> 2009 >> Equator Base, 4D Pickup >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (VQ40DE) - (4 Of 5) >> DTC P0031, P0032, P0051, P0052: A/F Sensor 1 Heater >> Diagnosis Procedure
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Diagnosis Procedure

DIAGNOSIS PROCEDURE

Step Action YES NO
CHECK GROUND CONNECTIONS 
  1. Turn ignition switch OFF.
  2. Loosen and retighten three ground screws on the body. Refer to [POWER SUPPLY AND GROUND CIRCUIT CHECK ].
G06441243Courtesy of SUZUKI OF AMERICA CORP.

OK or NG 
GO TO 2. Repair or Replace ground connections.
CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT 
  1. Disconnect air fuel ratio (A/F) sensor 1 harness connector.
G06441244G06441245Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

  1. 2. Turn ignition switch ON.
  2. 3. Check voltage between air fuel ratio sensor 1 terminal 4 and ground with SDT or tester.
G06441244G06441245Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

Voltage: Battery voltage 
OK or NG 
GO TO 4. GO TO 3.
DETECT MALFUNCTIONING PART 
Check the following.
  • Harness connectors E2, F32
  • IPDM E/R harness connector E119
  • 15 A fuse (No. 54)
  • Harness for open or short between air fuel ratio sensor 1 and fuse
Repair or replace harness or connectors.  
CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER OUTPUT SIGNAL CIRCUIT 
  1. Turn ignition switch OFF.
  2. Disconnect ECM harness connector.
  3. Check harness continuity between ECM terminal 2 (bank 1) or 24, 43 (bank 2) and air fuel ratio (A/F) sensor 1 terminal 3.

    Refer to WIRING DIAGRAM .

    Continuity should exist. 

  4. Also check harness for short to ground or short to power.

OK or NG 
GO TO 5. Repair open circuit or short to ground or short to power in harness or connectors.
CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER 
Refer to [P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER ].
OK or NG 
GO TO 6. GO TO 7.
CHECK INTERMITTENT INCIDENT 
Perform [SERVICE INFORMATION FOR ELECTRICAL INCIDENT: INTERMITTENT INCIDENT ]
OK or NG 
GO TO 7. Repair or replace.
REPLACE AIR FUEL RATIO (A/F) SENSOR 1 
Replace malfunctioning air fuel ratio (A/F) sensor 1.
INSPECTION END