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Home >> Suzuki >> 2012 >> Equator Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine General Information & Diagnosis - Qr25DE (2 Of 5) >> DTC P0131: A/F Sensor 1 >> Diagnosis Procedure
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Diagnosis Procedure

DIAGNOSIS PROCEDURE CHART

Step Action YES NO
1  CHECK GROUND CONNECTIONS 
  1. Turn ignition switch OFF.
  2. Loosen and retighten two ground screws on the body. Refer to [POWER SUPPLY AND GROUND CIRCUIT CHECK ].
G00538109Courtesy of SUZUKI OF AMERICA CORP.

OK or NG 		 GO TO 2. Repair or replace ground connections.
2  CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT 
  1. Disconnect A/F sensor 1 harness connector.
G06444074G06444075Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

  1. 2. Turn ignition switch ON.
  2. 3. Check voltage between A/F sensor 1 terminal 3 and ground with SDT or tester.
G06444074G06444075Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

Voltage: Battery voltage 
OK or NG 		 GO TO 4. GO TO 3.
3  DETECT MALFUNCTIONING PART 
Check the following.
  • Harness connectors E2, F32
  • IPDM E/R harness connector E119
  • 15A fuse (No. 54)
  • Harness for open or short between A/F sensor 1 and fuse
 Repair or replace harness or connectors.  
4  CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
  1. Turn ignition switch OFF.
  2. Disconnect ECM harness connector.
  3. Check harness continuity between the following terminals. Refer to WIRING DIAGRAM .
G06444076Courtesy of SUZUKI OF AMERICA CORP.

Continuity should exist. 
  1. 4. Check harness continuity between ECM terminals 16, 35, 56, 75 or A/F sensor 1 terminals 1, 2, 5, 6 and ground. Refer to WIRING DIAGRAM .

    Continuity should not exist. 

  2. 5. Also check harness for short to power.

OK or NG 		 GO TO 5. Repair open circuit, short to ground or short to power in harness or connectors.
5  CHECK INTERMITTENT INCIDENT 
Perform [SERVICE INFORMATION FOR ELECTRICAL INCIDENT: INTERMITTENT INCIDENT ]
OK or NG 		 GO TO 6. Repair or replace.
6  REPLACE AIR FUEL RATIO (A/F) SENSOR 1 
Replace air fuel ratio (A/F) sensor 1. Refer to [EXHAUST MANIFOLD AND THREE WAY CATALYST: EXPLODED VIEW [QR25DE] ].
CAUTION:
  • Discard any air fuel ratio (A/F) sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a hard surface such as a concrete floor; use a new one.
  • Before installing new air fuel ratio (A/F) sensor, clean exhaust system threads using Heated Oxygen Sensor Thread Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant (commercial service tool).
 INSPECTION END   
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