Inspection Procedure

CHECK HO2S AND ECM CONNECTORS
Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. See CONNECTOR INSPECTION PROCEDURE .

Are all connectors good?
1. Yes: Go to next step.
2. No: Repair or replace it.
CHECK HEATER RESISTANCE
1. Turn ignition switch to OFF position and disconnect HO2S connector.
2. Measure resistance between terminals 5 and 6 of the HO2S connector.
  Specification (HO2S resistance):
Fig 1: Heater Resistance Specifications
Courtesy of KIA MOTORS AMERICA, INC.

Fig 2: Checking Heater Resistance
Courtesy of KIA MOTORS AMERICA, INC.

Is resistance within specification?
1. Yes: Go to next step.
2. No: Replace HO2S.
CHECK POWER TO HO2S HEATER
1. Turn ignition switch to OFF position and disconnect HO2S connector.
2. Turn ignition switch to ON position.
3. Measure voltage between terminal 5 of the HO2S harness connector and chassis ground.
  Specification (Voltage): approximately B+
  
  Fig 3: Checking Heater Voltage
  Courtesy of KIA MOTORS AMERICA, INC.
Is voltage within specification?
1. Yes: Go to next step.
2. No: Repair open or short to chassis ground in harness.
CHECK FOR OPEN IN HARNESS
1. Turn ignition switch to OFF position, and then disconnect HO2S and ECM connector.
2. Measure resistance between terminal 6 of the HO2S harness connector and 8 of the ECM harness connector.
  Specification (Resistance): below 1Ω
  
  Fig 4: Checking For Open In Harness
  Courtesy of KIA MOTORS AMERICA, INC.
  
  Does the resistance indicate continuity?
  1. Yes: Go to next step.
  2. No: Repair open in harness.
3. CHECK FOR SHORT TO GROUND IN HARNESS
  1. Turn ignition switch to OFF position, and then disconnect HO2S and ECM connector.
  2. Measure resistance between terminal 6 of the HO2S harness connector and chassis ground.
    Specification (Resistance): infinite
    
    Fig 5: Checking For Short To Ground In Harness
    Courtesy of KIA MOTORS AMERICA, INC.
  Does the resistance indicate open?
  1. Yes: Go to next step.
  2. No: Repair short or short to chassis ground in harness.
4. CHECK FOR SHORT TO POWER IN HARNESS
  1. Turn ignition switch to OFF position, and the disconnect HO2S and ECM connectors.
  2. Turn ignition switch to ON position.
  3. Measure voltage between terminal 6 of the HO2S harness connector and chassis ground.
    Specification (Voltage): below 0.5V
    
    Fig 6: Checking For Short To Power In Harness
    Courtesy of KIA MOTORS AMERICA, INC.
  Is voltage within specification?
  1. Yes: Replace HO2S.
  2. No: Repair short to power in harness.