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DTC P2251-00: O2 Sensor Negative Current Control Circuit/Open - Bank 1, Sensor 1 [08/2018 - ]: Contents

DTC No. Detection Item DTC Detection Condition Warning Indicate Memory Fail-safe Operation Note
P225100 O2 Sensor Negative Current Control Circuit/Open - Bank 1, Sensor 1 Open circuit between A/F sensor terminal C6-5*1, C35-5*2 and ECM terminal C27-81*1, C28-4*2
  • Check engine light: ON
  • Master warning light: OFF
  • Charging system warning light: OFF
  • Engine oil warning light: OFF
  • Wrench warning indicator light: OFF
 DTC stored Not applicable
  • Drive cycle: 2
  • Monitor item: A/F sensor, HO2S
  • Self test type: CMDTC self test, KOER self test

*1: 200 Pin Type

*2: 186 Pin Type

DETAILS ON DTCS (200 PIN TYPE)

DTC DETECTION CONDITION Open circuit between A/F sensor terminal C6-5 and ECM terminal C27-81
Determination conditions
  • The following conditions are met:
    • A/F sensor element impedance is specified value or more
    • A/F sensor terminal C6-6 voltage (B+ terminal) is less than specified value or unstable.
Preconditions
  • Battery voltage: 11-18 V*
  • A/F sensor is activated.
  • The following DTCs are not detected:
    • A/F sensor terminal C6-6 voltage (B+ terminal) is less than specified value:
      1. A/F sensor heater: P003100, P003200
    • A/F sensor terminal C6-6 voltage (B+ terminal) is unstable:
      1. Internal ECM malfunction: P064D00
*: Value can be verified by displaying PIDs using Techstream
Drive cycle
  • 2
Self test type
  • CMDTC self test, KOER self test
Sensor used
  • A/F sensor
FAIL-SAFE OPERATION
  • Not applicable
VEHICLE STATUS WHEN DTCS ARE OUTPUT
  • Illuminates check engine light.
TROUBLE AREA
  • A/F sensor connector or terminals malfunction
  • ECM connector or terminals malfunction
  • Open circuit in wiring harness between A/F sensor terminal C6-5 and ECM terminal C27-81
  • A/F sensor malfunction
  • ECM malfunction
DETAILS ON DTCS (186 PIN TYPE)

DTC DETECTION CONDITION Open circuit between A/F sensor terminal C35-5 and ECM terminal C28-4
Determination conditions
  • The following conditions are met:
    • A/F sensor element impedance is specified value or more
    • A/F sensor terminal C35-6 voltage (B+ terminal) is less than specified value or unstable.
Preconditions
  • Battery voltage: 11-18 V*
  • A/F sensor is activated.
  • The following DTCs are not detected:
    • A/F sensor terminal C35-6 voltage (B+ terminal) is less than specified value:
      1. A/F sensor heater: P003100, P003200
    • A/F sensor terminal C35-6 voltage (B+ terminal) is unstable:
      1. Internal ECM malfunction: P064D00
*: Value can be verified by displaying PIDs using Techstream
Drive cycle
  • 2
Self test type
  • CMDTC self test, KOER self test
Sensor used
  • A/F sensor
FAIL-SAFE OPERATION
  • Not applicable
VEHICLE STATUS WHEN DTCS ARE OUTPUT
  • Illuminates check engine light.
TROUBLE AREA
  • A/F sensor connector or terminals malfunction
  • ECM connector or terminals malfunction
  • Open circuit in wiring harness between A/F sensor terminal C35-5 and ECM terminal C28-4
  • A/F sensor malfunction
  • ECM malfunction
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