378 problems have been reported for the 2020 Toyota Corolla. The following chart shows the 25 most common problems for 2020 Toyota Corolla. The number one most common problem is related to the vehicle's engine and engine cooling with 105 problems. The second most common problem is related to the vehicle's equipment (78 problems).
In our research we use the PPMY index to compare the reliability of vehicles. The PPMY index of a certain model is defined as the problems reported per thousand vehicles per Year. The total sales of the 2020 Toyota Corolla in the United States are 305,813 units [1]. If the total number of problems reported by Toyota Corolla owners in the last 6 years is 378, and the age of the vehicle is 6, the PPMY index can then be calculated as
PPMY Index = 378 / 305,813 / 6 * 1000 = 0.21.
For more information, refer to this page: A study of reliability comparison across Toyota Corolla model year vehicles.
The following chart shows the number of problems reported during each of the service years since the debut of the 2020 Toyota Corolla in 2020.
| Service Year | Number of Problems |
|---|---|
| 2026 | |
| 2025 | |
| 2024 | |
| 2023 | |
| 2022 | |
| 2021 | |
| 2020 |
When making the decision between buying a new or used Toyota Corolla, the following table can be used to compare the 2020 Toyota Corolla with the Toyota Corolla from other model years. Note that the number of problems reported for the 2020 Corolla is 378 while the average number of problems reported for the 31 model years of the Toyota Corolla is 430.