DTC P0420 Catalyst System Efficiency Below Threshold (Bank 1): DTC Detecting Condition
DTC DETECTION CONDITION REFERENCE CHART
| Item |
Detecting Condition |
Possible Cause |
| DTC Strategy |
- Check catalyst oxygen storage capacity by evaluation downstream O2 sensor fluctuations
|
- Exhaust gas leaks
- Faulty rear HO2S
- Faulty three way catalyst converter
|
| Enable Conditions |
- Coolant temperature > 74°C (165°F)
- 5km/h (3MPH) < Vehicle speed
- Ambient pressure > 525mmHg (70kPa)
- 1200rpm < Engine speed < 3500rpm
- 300 °C (572* F) ≤ Catalyst temp, model ≤ 730 °C (1346°F)
- Canister load < 0.5
- Lambda control / Forced stimulation active
- Engine operating state Part load
- Downstream O2 sensor operative ready
- No relevant failure
- 11V < Battery voltage < 16V
- Current engine speed - Mean of engine peed < 600 rpm
- Current mass air flow - Mean of mass air flow < 300 mg/rev
- Current lambda correction mean value - Mean of lambda correction mean value < 8%
|
| Threshold Value |
- Integral of VLS_DOWN - VLS_DOWN filtered > thd.
|
| Diagnostic Time |
- 20 forced stimulation cycles
|
| Mil On Condition |
|