| Case 1 |
Main Action |
- Plausibility check - characteristic line strong shift to rich
|
- Poor connection or damaged harness
- Front HO2S
|
| Prerequisite condition |
- Upstream O2 sensor operative readiness is detected.
- Downstream O2 sensor operative readiness is detected.
- Active test is not activated.
- Catalyst purge after fuel cut off is not active.
- Engine speed is higher than 600 rpm.
- Mass air flow is less than 83g/sec.
- Exhaust gas temperature model is between 300°C (572° F) and 800°C (1472°F).
|
| Threshold Value |
- Upstream lambda value is lower than 0.9 (rich).
- Downstream O2 signal voltage is lower than 0.2V (lean).
|
| Diagnosis Time |
|
| Case 2 |
Main Action |
- Plausibility check - characteristic line middle shift to rich
|
| Prerequisite condition |
- Fuel cut off is not active.
- Full load is not active. (accelerator pedal value is lower than 90%)
- Battery voltage is between 11V and 16V.
|
| Threshold Value |
- Upstream lambda value is smaller than 1.05. (when lambda set point equals to 1.15)
|
| Diagnosis Time |
- 10 Seconds after lambda set point shifted to corresponding side
|
| MIL On Condition |
|