Monitor Description
OUTLINE OF DIAGNOSIS
Detect that α value remains lean.
Judge as NG when lambda value is determined as abnormal in accordance with driving conditions such as intake air amount, rear oxygen element impedance, main feedback control, and with front air fuel ratio sensor α value.
| α value = Actual air fuel ratio/Theoretical air fuel ratio α > 1: Lean α < 1: Rich |
COMPONENT DESCRIPTION
| *A | Electromotive force | *B | Air fuel ratio |
| *C | Rich | *D | Lean |
| *1 | Exhaust gas | *2 | Zirconia element oxygen |
EXECUTION CONDITION
| Secondary parameters | Execution condition |
|---|---|
| Battery voltage | 10.9 V or higher |
| Main feedback | In operation |
| Amount of intake air | 6 g/s (0.21 oz/s) or more |
| Rear oxygen element impedance | 185 Ω or less |
GENERAL DRIVING CYCLE
Perform the diagnosis continuously after the enable conditions have been established.
DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Judgment value
| Malfunction Criteria | Threshold Value |
|---|---|
| α value | More than 1.15 |
| Output voltage value of heated oxygen sensor | Higher than 0.55 V |
Time needed for diagnosis
10000 ms
Malfunction indicator light illumination
Illuminates when malfunction occurs in 2 continuous driving cycles.