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Home >> Suzuki >> 2012 >> Equator RMZ-4 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Performance - VQ40DE - (5 Of 6) >> DTC P0133, P0153: A/F Sensor 1 >> Diagnosis Procedure
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Diagnosis Procedure

DIAGNOSIS PROCEDURE

Step Action YES NO
1  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 ].
G06441328Courtesy of SUZUKI OF AMERICA CORP.

OK or NG 		 GO TO 2. Repair or replace ground connections.
2  RETIGHTEN AIR FUEL RATIO (A/F) SENSOR 1 
Loosen and retighten A/F sensor 1. Refer to [EXHAUST MANIFOLD: REMOVAL AND INSTALLATION [VQ40DE] ]		 GO TO 3.  
3  CHECK EXHAUST GAS LEAK 
  1. Start engine and run it at idle.
  2. Listen for an exhaust gas leak before three way catalyst (manifold).
G06441329Courtesy of SUZUKI OF AMERICA CORP.

OK or NG 		 GO TO 4. Repair or replace.
4  CHECK FOR INTAKE AIR LEAK 
Listen for an intake air leak after the mass air flow sensor.
OK or NG 		 GO TO 5. Repair or replace.
5  CLEAR THE SELF-LEARNING DATA 
  1. With SDT 
    1. Start engine and warm it up to normal operating temperature.
    2. Select "SELF-LEARNING CONT" in "Utility" mode with SDT.
    3. Clear the self-learning control coefficient by touching "Clear" or "START".
    4. Run engine for at least 10 minutes at idle speed.

      Is the 1st trip DTC P0171, P172, P0174 or P0175 detected? Is it difficult to start engine? 

  2. Without SDT 
    1. Start engine and warm it up to normal operating temperature.
    2. Turn ignition switch OFF.
    3. Disconnect mass air flow sensor harness connector.
G06441330Courtesy of SUZUKI OF AMERICA CORP.

  1. 4. Restart engine and let it idle for at least 3 seconds.
  2. 5. Stop engine and reconnect mass air flow sensor harness connector.
  3. 6. Check DTC P0102 is displayed.
  4. 7. Erase the DTC memory. Refer to [On Board Diagnosis Function ] (Without SDT) or [SDT Function ] (With SDT).
  5. 8. Check DTC P0000 is displayed.
  6. 9. Run engine for at least 10 minutes at idle speed.

    Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected? Is it difficult to start engine? 


Yes or No 		 Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to DTC P0171, P0174: Fuel Injection System Function or DTC P0172, P0175: Fuel Injection System Function . GO TO 6.
6  CHECK A/F SENSOR 1 POWER SUPPLY CIRCUIT 
  1. Turn ignition switch OFF.
  2. Disconnect A/F sensor 1 harness connector.
G06441331G06441332Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

  1. 3. Turn ignition switch ON.
  2. 4. Check voltage between A/F sensor 1 terminal 4 and ground with SDT or tester.
G06441331G06441332Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

Voltage: Battery voltage 
OK or NG 		 GO TO 8. GO TO 7.
7  DETECT MALFUNCTIONING PART 
Check the following.
  • Harness connectors E2, F32
  • IPDM E/R connector E119
  • 15 A fuse (No. 54)
  • Harness for open or short between A/F sensor 1 and fuse
 Repair or replace harness or connectors.  
8  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 A/F sensor 1 terminal and ECM terminal as follows.

    Refer to WIRING DIAGRAM .

G06441333G06441334Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

Continuity should exist. 
  1. 4. Check harness continuity between the following terminals and ground. Refer to WIRING DIAGRAM .
G06441333G06441334Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

Continuity should not exist. 
  1. 5. Also check harness for short to power.

OK or NG 		 GO TO 9. Repair open circuit or short to ground or short to power in harness or connectors.
9  CHECK A/F SENSOR 1 HEATER 
Refer to [P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER ].
OK or NG 		 GO TO 10. GO TO 13.
10  CHECK MASS AIR FLOW SENSOR 
Refer to [P0101 MAF SENSOR ].
OK or NG 		 GO TO 11. Replace mass air flow sensor.
11  CHECK PCV VALVE 
Refer to [POSITIVE CRANKCASE VENTILATION CIRCUIT CHECK ].
OK or NG 		 GO TO 12. Repair or replace PCV valve.
12  CHECK INTERMITTENT INCIDENT 
Perform [SERVICE INFORMATION FOR ELECTRICAL INCIDENT: INTERMITTENT INCIDENT ]
OK or NG 		 GO TO 13. Repair or replace.
13  REPLACE A/F SENSOR 1 
Replace malfunctioning A/F sensor 1. Refer to EXHAUST MANIFOLD AND THREE WAY CATALYST: EXPLODED VIEW [VQ40DE] .
CAUTION:
  • Discard any 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 A/F sensor, clean exhaust system threads using Heated Oxygen Sensor Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
 INSPECTION END   
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