In back-to-back testing of an engine control unit, the model uses double-precision floating-point arithmetic, while the generated code uses single-precision floats. Test outputs differ slightly. What is the most appropriate action?

Change the code to use double precision

Treat any difference as a failure

Run the tests only on the model

Set a tolerance that accounts for the precision difference

In automotive software testing, back-to-back testing is specifically used to:

Compare the outputs of two different implementations of the same specification.

Detect differences between the behavior of a model and the behavior of the code generated from that model.

Test the software in a closed-loop environment with real-time hardware.

Verify that the software meets performance requirements under maximum load.

How are acceptable differences between model and code outputs typically handled in back-to-back testing?

By modifying the model to match the code's outputs.

By re-running the tests until the outputs match exactly.

By applying tolerances to the comparison.

By ignoring all differences and focusing only on functional behavior.

Which of the following is a common source of differences between model and code behavior in back-to-back testing?

The model being executed on a different operating system than the code.

Different test cases used for the model and the code.

Floating-point arithmetic rounding errors.

The code being written in a different programming language than the model.

A team is performing back-to-back testing on a vehicle dynamics model. They execute the same test cases on both the model and the generated code. What is the primary purpose of this activity?

To test the model's performance

To verify that the code behaves like the model

Certified Tester Automotive Software Tester

Domain 4Objective 3

Back-to-Back-Testing CT-AUT Practice Questions (Page 2)

Part of the Automotive-specific static and dynamic test techniques domain, which makes up ~20% of our current practice bank. ISTQB does not publish an official question count, but from its 60-minute exam (~25–40 total, ~5–8 in this domain), expect 1–1 from this objective — we provide 18 practice questions to prepare you well beyond it. (estimate)

18questions here

4free pages

5concepts

Questions 6–10

6application · medium
In back-to-back testing of an engine control unit, the model uses double-precision floating-point arithmetic, while the generated code uses single-precision floats. Test outputs differ slightly. What is the most appropriate action?
Select an answer first
7foundation · easy
In automotive software testing, back-to-back testing is specifically used to:
Select an answer first
8foundation · easy
How are acceptable differences between model and code outputs typically handled in back-to-back testing?
Select an answer first
9foundation · easy
Which of the following is a common source of differences between model and code behavior in back-to-back testing?
Select an answer first
10application · easy
A team is performing back-to-back testing on a vehicle dynamics model. They execute the same test cases on both the model and the generated code. What is the primary purpose of this activity?
Select an answer first

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