Protective coatings are widely used in applications that require high reliability of electronics. Thermal shock tests are used to verify the reliability of these coated electronics in the field. During this work, the effects of certain production parameters on the formation of faults in conforming coatings during thermal shock tests are investigated. The results particularly highlight that production residues contribute to failures during thermal shock tests and using cleaning procedures has a positive effect on performing well in these tests. This paper also provides a ranking of the relevant contributions to good thermal shock performance.