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Home >> Hyundai >> 2021 >> Veloster N Standard Trans >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (3 Of 3) >> DTC P2251-00: O2 Sensor Reference Ground Circuit/Open (Bank 1 Sensor 1) >> Wiring Inspection >> Control Circuit Inspection
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Control Circuit Inspection

Check Item Specifications Prerequisite Condition Terminal (+) Terminal (-)
Control Circuit - Voltage Approx. 2~3V
  1. Disconnect HO2S connector
  2. Ignition SW 'ON'
Vg terminal of HO2S harness Chassis GND
Check Item Specifications Prerequisite Condition Terminal (+) Terminal (-)
Control Circuit - Resistance Infinite (∞)
  1. Ignition SW 'OFF'
  2. Disconnect HO2S connector
Vg terminal of HO2S harness Other terminal of HO2S harness
  1. Is HO2S display near the specification?

    YES 

    • Go to next step below.

    NO 

NOTE: HO2S must have a clean air reference to function properly. The air is obtained by way of the sensor wire(s). Do not attempt to repair the wire(s), connector, or the terminals.