P1155

DTC P1155 - O2 SENSOR CIRCUIT RANGE/PERFORMANCE (HIGH) (BANK 2 SENSOR 1)

OUTLINE OF DIAGNOSIS
Detect that lambda value remains High.
Judge NG when lambda value is abnormal in accordance with lambda value of front oxygen (A/F) sensor and running condition that is vehicle speed, amount of intake air engine coolant temperature, sub feedback control, etc.

Lambda value = Actual air fuel ratio/Theoretical air fuel ratio
Lambda > 1: Lean
Lambda < 1: Rich




COMPONENT DESCRIPTION




ENABLE CONDITION

GENERAL DRIVING CYCLE
Perform diagnosis continuously at a constant speed of 20 km/h (12 MPH) or more since 60 seconds after starting the engine.

DIAGNOSTIC METHOD




Judge NG when the continuous time of completing the malfunction criteria becomes more than the time needed for diagnosis (10 seconds). Judge OK and clear NG when the malfunction criteria are not completed.

DTC CLEAR CONDITION
- When the OK idling cycle was completed 40 times in a row
- When " Clear Memory " was performed

MALFUNCTION INDICATOR LIGHT CLEAR CONDITION
- When the OK driving cycle was completed 3 times in a row
- When " Clear Memory " was performed

FAIL SAFE
- Front oxygen (A/F) sensor main learning correction: Not allowed to calculate.
- Rear oxygen sensor sub learning correction: Not allowed to calculate.
- Correction when re-starting at high temperature: Normally minimum value 0.06 -> 0
- Purge control: Not allowed to purge

ECM OPERATION AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)