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Home >> Toyota >> 2019 >> Yaris LE >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Diagnostic Codes (12 Of 13) >> SFI System >> DTC P2251-00: O2 Sensor Negative Current Control Circuit/Open - Bank 1, Sensor 1 [07/2015 - 08/2018] >> Caution / Notice / Hint
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Caution / Notice / Hint

HINT: 

Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

  1. PID Item/Simulation Item Used In Diagnosis 
    PID/DATA MONITOR ITEM TABLE

    Item Definition Unit Condition/Specification
    Heated Exhaust Gas Oxygen Sensor (bank 1, sensor 1) A/F sensor current μA
    • Idle (after warm up): 0-50 μA
    • Deceleration fuel cut (accelerator pedal released from engine speed of 4000 rpm or more): Approx. 3.84 mA
  2. Intention of troubleshooting procedure 
    • Step 6-7
      • Verify that the primary malfunction is resolved and there are no other malfunctions.