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Home >> Suzuki >> 1999 >> Swift Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0134: Heated Oxygen Sensor (Ho2S) No. 1 Circuit/No Activity Detected
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DTC P0134: Heated Oxygen Sensor (Ho2S) No. 1 Circuit/No Activity Detected

NOTE: If any DTCs besides DTC P0134, P0171 or P0172 are set, diagnose those DTCs first.
  1. Connect scan tool to Data Link Connector (DLC). Start engine and allow it to reach normal operating temperature. Increase engine speed to 2000 RPM for at least 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 display reading does not vary from less than 0.3 volt to greater than 0.6 volt, go to next step. If display reading varies from less than 0.3 volt to greater than 0.6 volt, check fuel system. See DTC P0171: FUEL SYSTEM LEAN OR DTC P0172: FUEL SYSTEM RICH  .
  2. On Esteem, check White and Orange wires between HO2S No. 1 and PCM for an open or short circuit. On Swift, check Red and Light Green/Black wires between HO2S No. 1 and PCM for an open or short circuit. Repair as necessary. If wires are okay, replace HO2S No. 1. Retest system.
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