GDS Data Analysis

Connect GDS and select "DTC Analysis" mode
Warm up the engine.
Monitor the parameters related to DTC on the "Current Data" menu of the GDS below while press and depress gas pedal.

Fig 1: Screen Display - Downstream O2 Sensor Service Data Review
Courtesy of HYUNDAI MOTOR AMERICA

A sector: acceleration → open loop fuel control → downstream O2 sensor' data represents lean state
Is parameter displayed within specifications?
YES
- Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair " procedure.
NO
- Go to next step.