Typical Enabling Conditions
| Diagnosis 1 | Overlap prohibited DTC | |
| Soak time | 21600 seconds or more | |
| Engine Speed | 500 r/min or more | |
| Block heater judgment | Complete | |
| Block heater operation | Not operating |
| Block heater judgment Duration while rear oxygen sensor output voltage is less than 0.55 V |
500 r/min or more |
| When conditions are met, the state is judged as "Block heater is not operating". Σ (engine coolant temp. - engine coolant temp. at engine startup) Time required for judgment: 1 sec. X20 times (per second) |
-10°C (-18°F) or more |
| Diagnosis 2 | Engine oil temperature at engine start | 50°C {122°F} or less |
| Engine Speed | 500 r/min or more | |
| Idling ratio | 0.5 or less |