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Home >> Suzuki >> 2006 >> Grand Vitara Premium, RWD, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine General Information And Diagnosis >> Diagnostic Information And Procedures >> DTC P0037/P0038: Ho2S Heater Control Circuit Low/High (Sensor-2, Bank-1) >> DTC Troubleshooting
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DTC Troubleshooting

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  A/F sensor DTC check 
Are there DTC P0031 and/or P0051? 		 Go to applicable DTC flow referring to DTC P0031/P0032: HO2S HEATER CONTROL CIRCUIT LOW/HIGH (SENSOR-1, BANK-1)  and/or DTC P0051/P0052: HO2S Heater Control Circuit Low/High (Sensor-1, Bank-2) . Go to Step 3.
3  HO2S heater relay and its circuit check 
  1. Disconnect connector from HO2S (bank-1) with ignition switch turned OFF.
  2. Check for proper terminal connection to HO2S (bank-1) connector.
  3. If connections are OK, check that HO2S (bank-1) heater control circuit is as follows.
    • Circuit voltage between "Power supply circuit of HO2S (bank-1) heater" and vehicle body ground is battery voltage with ignition switch turned ON.

Is it in good condition? 		 Go to Step 4 Repair or replace defective wiring harness.
4  HO2S heater circuit check 
  1. Check that HO2S (bank-1) heater control circuit is as follows.
    • Circuit voltage between "Control circuit of HO2S (bank-1) heater" and vehicle body ground is 0 V with ignition switch turned ON.

Is it good condition? 		 Go to Step 5. Repair or replace defective wiring harness.
5  HO2S heater circuit check 
  1. Disconnect connectors form ECM and check for proper terminal connection to ECM connector.
  2. If connections are OK, check that HO2S (bank-1) heater circuit is as follows.
    • Insulation resistance of wire harness is infinity between "Control circuit of HO2S (bank-1) heater" terminal and each other terminal at HO2S (bank-1) connector.
    • Wiring harness resistance of "Control circuit of HO2S (bank-1) heater" is less than 1 Ω.
    • Insulation resistance between "Control circuit of HO2S (bank-1) heater" and vehicle body ground is infinity.

Is it in good condition? 		 Go to Step 6. Repair or replace defective wiring harness.
6  HO2S heater check 
  1. Check heater resistance of HO2S (bank-1) referring to HEATED OXYGEN SENSOR (HO2S-2) HEATER ON-VEHICLE INSPECTION .

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