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Home >> Suzuki >> 2002 >> Esteem GL, 4D Sedan, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 1.8L >> Diagnostic Tests >> DTC P0131 Or DTC P0132 >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. If engine system check has been performed, go to next step. If engine system check has not been performed, go to A4: ENGINE SYSTEM CHECK  under SYSTEM TESTS.
  2. Turn ignition on. Ensure that fuel tank is not empty. If fuel tank is empty, add fuel and repeat DTC CONFIRMATION TEST  . If fuel tank is not empty, go to next step.
  3. Start engine and allow it to reach normal operating temperature. Increase engine speed to 2000 RPM for one minute. Allow engine to return to idle. Rapidly increase engine speed 5-6 times repeatedly while monitoring HO2S No. 1 parameter on scan tool. If parameter does not vary from less than 0.4 volt to more than 0.6 volt, go to next step. If parameter varies from less than 0.4 volt to more than 0.6 volt, go to step  8 .
  4. Turn ignition off. Disconnect HO2S No. 1 4-pin harness connector. HO2S No. 1 is located in exhaust pipe before catalytic convertor. Check for poor terminal contact at HO2S No. 1 pigtail and harness connector. If problem is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST  . If no problem is found, go to next step.
  5. Using DVOM, measure voltage between HO2S No. 1 pigtail terminals No. 1 (Orange wire) and No. 2 (White wire). See Fig 1 . Rapidly increase engine speed 5-6 times repeatedly while monitoring HO2S No. 1 voltage. If voltage does not vary from less than 0.4 volt to more than 0.6 volt, replace HO2S No. 1. After repair, repeat DTC CONFIRMATION TEST  . If voltage varies from less than 0.4 volt to more than 0.6 volt, go to next step.
  6. Check for open or short in Orange wire between HO2S No. 1 harness connector terminal No. 1 and ECM harness connector C20 terminal No. 27. See Figure and Fig 1 . Also, check for open or short in White wire between HO2S No. 1 harness connector terminal No. 2 and ECM harness connector C20 terminal No. 4. If problem is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST  . If no problem is found, go to next step.
  7. Substitute a known good ECM, and repeat DTC CONFIRMATION TEST  . If DTC does not reset, testing is complete.
  8. Operate engine at 2000 RPM for one minute. Reduce engine to idle speed. Using scan tool, check SHORT TERM FUEL TRIM parameter. If parameter is between -20 and +20 percent, problem is probably intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. If parameter is not as specified, check fuel trim system. Go to DTC P0171 OR DTC P0172  .
Fig 1: Identifying Heated Oxygen Sensor Nos. 1 & 2 Pigtail Connector Terminals
G00163659Courtesy of SUZUKI OF AMERICA CORP.
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