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Home >> Hyundai >> 2017 >> Azera Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (1 Of 3) >> DTC P0031: HO2S Heater Control Circuit Low (Bank 1/Sensor 1) >> W/Harness Inspection >> Control Circuit Inspection
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Control Circuit Inspection

■ Check short to ground 

  1. IG "OFF" & Disconnect HO2S (B1/S1) connector.
  2. Measure resistance between control terminal of HO2S (B1/S1) heater harness connector and chassis ground.

    Specification:  Infinite

    Fig 1: Measuring Resistance Between Control Terminal Of HO2S (B1/S1) Heater Harness Connector And Chassis Ground
    G12087245Courtesy of HYUNDAI MOTOR AMERICA
  3. Is the measured resistance within specification?

    YES 

    NO 

■ Check open in harness 

  1. IG "OFF" and disconnect HO2S (B1/S1) and PCM connector.
  2. Measure resistance between control terminal of HO2S (B1/S1) heater harness connector and heater control terminal of PCM harness connector.

    Specification:  Approx. below 1 Ω

    Fig 2: Measuring Resistance Between Control Terminal Of HO2S (B1/S1) Heater Harness Connector And Heater Control Terminal Of PCM Harness Connector
    G12087246Courtesy of HYUNDAI MOTOR AMERICA
  3. Is the measured resistance within specification?

    YES 

    NO