HO2S Monitor
OPERATION (1 OF 2)
| DTC | P0139 |
| Monitor execution | Once per driving cycle |
| Monitoring duration | Not applicable |
OPERATION (2 OF 2)
| DTC | P2A01 |
| Monitor execution | Continuous |
| Monitoring duration | 15 sec. (Monitor 1), Not applicable (Monitor 2), 40 sec. (Monitor 3, Monitor 4) |
ENABLE CONDITIONS
| Parameter | Min. | Max. |
|---|---|---|
| P0139 | ||
| Fuel shut off | 8 sec. | - |
| HO2S heater on | 200 sec. | - |
| HO2S voltage at monitor start | 0.64 V | - |
| HO2S | No DTC (P0137, P0138) | |
| HO2S heater | No DTC (P0037, P0038) | |
| P2A01 | ||
| Monitor 1 | ||
| Lambda (A/F) after fuel shut off | - | 0.95 |
| HO2S heater on | 200 sec. | - |
| A/F sensor | No DTC (P0131, P0132, P2237) | |
| HO2S | No DTC (P0137, P0138) | |
| HO2S heater | No DTC (P0037, P0038) | |
| Monitor 2 | ||
| Time from fuel shut off | 8 sec. | - |
| HO2S heater on | 200 sec. | - |
| A/F sensor | No DTC (P0131, P0132, P2237) | |
| HO2S | No DTC (P0137, P0138) | |
| HO2S heater | No DTC (P0037, P0038) | |
| Monitor 3, Monitor 4 | ||
| Sub feedback | Closed loop | |
| HO2S voltage Max - Min | - | 0.2 V |
| HO2S heater on | 200 sec. | - |
| MAF | 10 g/sec. | - |
| A/F sensor | No DTC (P0131, P0132, P2237) | |
| HO2S | No DTC (P0137, P0138) | |
| HO2S heater | No DTC (P0037, P0038) | |
| ECT | 70 °C (158 °F) | - |
TYPICAL MALFUNCTION THRESHOLDS
| P0139: Switch time from 0.6 V to 0.3 V > 0.5 sec. | |
| P2A01 | |
| Monitor 1: | HO2S voltage < 0.64 V |
| Monitor 2: | HO2S voltage > 0.1 V |
| Monitor 3: | HO2S voltage < 0.4 V |
| Monitor 4: | HO2S voltage > 0.85 V |