55 problems have been reported for the 2009 Lexus IS. The following chart shows the 17 most common problems for 2009 Lexus IS. The number one most common problem is related to the vehicle's equipment with 15 problems. The second most common problem is related to the vehicle's vehicle speed control (10 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 2009 Lexus IS in the United States are 31,875 units [1]. If the total number of problems reported by Lexus IS owners in the last 17 years is 55, and the age of the vehicle is 17, the PPMY index can then be calculated as
PPMY Index = 55 / 31,875 / 17 * 1000 = 0.10.
For more information, refer to this page: A study of reliability comparison across Lexus IS model year vehicles.
The following chart shows the number of problems reported during each of the service years since the debut of the 2009 Lexus IS in 2009.
| Service Year | Number of Problems |
|---|---|
| 2026 | |
| 2025 | |
| 2024 | |
| 2023 | |
| 2022 | |
| 2021 | |
| 2020 | |
| 2019 | |
| 2018 | |
| 2017 | |
| 2016 | |
| 2015 | |
| 2014 | |
| 2013 | |
| 2012 | |
| 2011 | |
| 2010 | |
| 2009 |
When making the decision between buying a new or used Lexus IS, the following table can be used to compare the 2009 Lexus IS with the Lexus IS from other model years. Note that the number of problems reported for the 2009 IS is 55 while the average number of problems reported for the 26 model years of the Lexus IS is 30.