More than likely your customer asked you about VDA 6.3 process audits. A company cannot be certified to this standard. Either you perform this process (or contract out) (can be pretty lengthy and requires training to do it right) or your customer comes in and does the audit.
VDA 6.3 has over 70 questions that will be judged with a score of 10,8,6,4 or 0. Resulting scores of all questions are combined into a A, B or C classification.
You can purchase the VDA 6.3 2nd edition from
www.vda-qmc.de website.