C1551: Battery voltage abnormal rise/drop
Short answer: C1551 means “Battery voltage abnormal rise/drop”. Below is what it means on each of the 2 cars we cover, with a link to the full page for each car.
C1551 on each car
| Car | Meaning on this car | Confidence |
|---|---|---|
| Toyota Passo (1st gen) | Battery voltage abnormal rise/drop (C1551/51) | high |
| Toyota Corolla (9th gen, E120) | IG Power Source Circuit Malfunction (C1551/51) | high |
Symptoms
- Warning lamp per chart (see page)
Likely causes
- Battery voltage abnormal rise/drop
What to check, in order
- Follow manual section procedure for this code
Causes and checks above are the general meaning. The exact test steps and values differ by car: open your car’s page.