Cadillac ATS owners have reported a total of 277 problems for their cars built in the
6 model years
listed in the chart below.
The chart shows the number of problems reported across all service years for each given model year of the Cadillac ATS.
The 2013 Cadillac ATS cars have the most problems reported (169 problems).

Table 1. Total number of problems by model year for Cadillac ATS

The following chart shows the 20 most common problems for Cadillac ATS cars.
The number one most common problem is related to the vehicle's engine and engine cooling
(51 problems).
The second most common problem is related to the vehicle's electrical system (39 problems).

Compare Reliability Across Model Years Using PPMY Index

It would not be fair to compare the Cadillac ATS of an older model year to newer model years
since older vehicles have been in service longer and thus are expected to have more problems.
In order to compare the reliability across ATS model years, we use the PPMY index which is defined as the
problems reported per thousand vehicles per Year.
A smaller PPMY index indicates greater reliability of the given model year cars.

PPMY = P / S / Y * 1000,

where P = total problems reported during the life of a Cadillac ATS model year;
S = total units sold of the model year; Y = years since the debut of the model year (the age of the vehicle).

The results are shown in Table 3.

Table 3. Use PPMY Index to Compare Reliability Across ATS Model Years

Another way to measure the reliability across the model years of the Cadillac ATS
is to use the total number of problems reported during the vehicle's first year in service, as shown in the Table 4.

Table 4. Number of problems in vehicle's; first service year