2004 Hyundai Tiburon Base, StandardFACTORY OEM SERVICE PROCEDURE

Inspection Procedures

  1. PROBLEM VERIFICATION
    1. Connect Hi-Scan (Pro) to data link connector and warm up engine to normal operating temperature.
    2. Using Hi-Scan (Pro), monitor HO2S signal.

    Does the HO2S signal switch from lean to rich or from rich to lean? 

    Yes: Go to next

    No: Repair or replace it.

  2. CHECK HO2S HEATER RESISTANCE
    1. Turn ignition switch to OFF and disconnect HO2S connector.
    2. Measure resistance between the terminals 3 and 4 of HO2S connector.
    Fig 1: Measuring Resistance Between Terminals 3 & 4 Of HO2S Connector
    G00893188Courtesy of HYUNDAI MOTOR CO.
    • 9ohm at between 20°C ~ 24°C (68°F ~ 75.2°F)

    Is resistance within specification? 

    Yes: Go to next

    No: Replace HO2S.

  3. CHECK POWER TO HO2S HEATER
    1. Turn ignition switch to ON position.
    2. Measure voltage between terminal 4 of the HO2S harness connector and chassis ground.
    Fig 2: Measuring Voltage Between Terminal 4 Of HO2S Harness Connector & Chassis Ground
    G00893189Courtesy of HYUNDAI MOTOR CO.
    • Specification: approximately B+ 

    Is voltage within specification? 

    Yes: Go to next

    No: Repair open or short to ground in harness.

  4. CHECK FOR SHORT TO GROUND IN HARNESS
    1. ECM and HO2S connectors are still disconnected.
    2. Measure resistance between terminal 3 of HO2S harness connector and chassis ground.
    Fig 3: Measuring Resistance Between Terminal 3 Of HO2S Harness Connector & Chassis Ground
    G00893190Courtesy of HYUNDAI MOTOR CO.
    • Specification: infinite 

Does resistance indicate open? 

Yes: Proceed with ECM PROBLEM PROCEDURE  .

No: Repair short to chassis ground in harness.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.