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Home >> Suzuki >> 2007 >> SX4 Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 151 (Engine General Information And Diagnosis) >> Diagnostic Information And Procedures >> DTC P0140: O2 Sensor Circuit No Activity Detected (Sensor-2, Bank-1) >> DTC Troubleshooting
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DTC Troubleshooting

WARNING: This page is about a different car, the 2006 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to PRECAUTIONS FOR DTC TROUBLESHOOTING .
DTC TROUBLESHOOTING CHART

Step Action YES NO
1 Was "Engine and Emission Control System Check" performed?  Go to Step 2. Go to ENGINE AND EMISSION CONTROL SYSTEM CHECK .
2 HO2S signal check 
  1. Connect scan tool with ignition switch turned OFF
  2. Warm up engine to normal operating temperature and keep it at 2000 r/min. for 60 sec.
  3. Repeat racing engine (Repeat depressing accelerator pedal 5 to 6 times continuously to enrich A/F mixture and take foot off from pedal to enlean it).
  4. Check for HO2S (bank-1) output voltage displayed on scan tool.

Does HO2S output voltage between 0.5 V and 0.8 V? 		 Intermittent trouble. Check for intermittent referring to INTERMITTENT AND POOR CONNECTION INSPECTION . Go to Step 3.
3 HO2S circuit check 
  1. Disconnect connector from HO2S (bank-1) and ECM with ignition switch turned OFF.
  2. Check for proper terminal connection to HO2S (bank-1) connector and ECM connector.
  3. If connections are OK, check that HO2S (bank-1) circuit is as follows.
    • Wiring harness resistance of each "Signal circuit of HO2S (bank-1)", "Ground circuit of HO2S (bank-1)" and "Control circuit of HO2S (bank-1) heater" is less than 1 Ω.
    • Insulation resistance between "Signal circuit of HO2S (bank-1)" and vehicle body ground is infinity.
    • Insulation resistance of wire harness is infinity between "Signal circuit of HO2S (bank-1)" terminal and each other terminal at HO2S (bank-1) connector.
    • Circuit voltage between "Signal circuit of HO2S (bank-1)" and vehicle body ground is 0 V with ignition switch turned ON.

Are they in good condition? 		 Go to Step 4. repair or replace defective wiring harness.
4 HO2S heater check 
  1. Check heater resistance of HO2S (bank-1) referring to HEATED OXYGEN SENSOR (HO2S-2) HEATER ON-VEHICLE INSPECTION .

Is HO2S heater in good condition? 		 Substitute a known-good ECM and recheck. If ECM OK, replace HO2S (bank-1). Replace HO2S (bank-1).
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