DTC P2270-19: A/F (O2) Sensor Signal Biased/Stuck Lean Bank 1 Sensor 2 Circuit Current Above Threshold; DTC P2271-18: A/F (O2) Sensor Signal Biased/Stuck Rich Bank 1 Sensor 2 Circuit Current Below Threshold [08/2023 - ]: Description
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Refer to DTC P0036-12.
Refer to DESCRIPTION
HINT:
Although the DTC title say O2 sensor, these DTCs relate to the air fuel ratio sensor (sensor 2).
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | DTC Output from | Priority | Note |
|---|---|---|---|---|---|---|---|
| P2270-19 | A/F (O2) Sensor Signal Biased/Stuck Lean Bank 1 Sensor 2 Circuit Current Above Threshold | While the fuel-cut operation is performed (during vehicle deceleration), the air fuel ratio sensor (sensor 2) current is 33.13 mA or more for 0.5 seconds or more (2 trip detection logic). |
|
Comes on | Engine | B |
|
| P2271-18 | A/F (O2) Sensor Signal Biased/Stuck Rich Bank 1 Sensor 2 Circuit Current Below Threshold | While the fuel-cut operation is performed (during vehicle deceleration), the air fuel ratio sensor (sensor 2) current is less than 7.5 mA for 0.5 seconds or more (2 trip detection logic). |
|
Comes on | Engine | B |
|
HINT:
- When any of these DTCs are stored, check the air fuel ratio sensor (sensor 2) current output by entering the following menus on the GTS: Powertrain / Engine / Data List / A/F (O2) Sensor Current B1S2.
- Short-term fuel trim values can also be read using the GTS.
- If an air fuel ratio sensor (sensor 2) malfunction is detected, the ECM will store a DTC.