Diagnostic Method
When TWC performance degrade, OSC performance also degrades. A malfunction is detected by diagnosis that estimates OSC performance based on the time and air volume required from the deceleration fuel cut for the predetermined time or longer until the start of increase in the rear oxygen sensor voltage.
JUDGMENT VALUE SPECIFICATION
| Malfunction Criteria | Threshold Value |
|---|---|
| Oxygen Storage Capacity (OSC) of Catalytic | Less than 0.2g (0.01oz) |
Time needed for diagnosis: Less than 1 s
Malfunction indicator light illumination: Illuminates when malfunction occurs in 2 continuous driving cycles.