| One of the following conditions is met |
Conditions A, B, C or D |
| A. All of the following conditions are met |
- |
| EGR1 output terminal voltage |
Low |
| Either of the following conditions is met |
1 or 2 |
| 1. Step motor |
Driving |
| 2. EGR1 |
Not operating |
| B. All of the following conditions are met |
- |
| EGR2 output terminal voltage |
Low |
| Either of the following conditions is met |
3 or 4 |
| 3. Step motor |
Driving |
| 4. EGR2 |
Not operating |
| C. All of the following conditions are met |
- |
| EGR3 output terminal voltage |
Low |
| Either of the following conditions is met |
5 or 6 |
| 5. Step motor |
Driving |
| 6. EGR3 |
Not operating |
| D. All of the following conditions are met |
- |
| EGR4 output terminal voltage |
Low |
| Either of the following conditions is met |
7 or 8 |
| 7. Step motor |
Driving |
| 8. EGR4 |
Not operating |