QM Knowledge: NTF

• Definition
• Content of the NTF process
• Relevance for Companies

The "No Trouble Found" process, or NTF, is part of the damaged parts analysis process, which in turn is under the CIP (Continuous Improvement Process). The term is mainly used in the manufacturing industry, especially in the automotive industry. Together with "Planning", "Findings" and "Process Problem Analysis", the "No Trouble Found" process forms the Defective Part Analysis and is intended to ensure that a defect can be identified in all categories. The defect can be located directly on the part, in the system, or in the process.

The term "No Trouble Found" refers to the following situation: A product is returned to the manufacturer by the user due to a defect that has occurred. The user expects the faulty product to be repaired or replaced. However, when the manufacturer inspects the product, he cannot detect any problem with the product; the device functions perfectly. His verdict is therefore: "No Trouble Found".

With the NTF process, the VDA standard (Verband der Automobilindustrie e. V. – German Association of the Automotive Industry) includes a methodical procedure for dealing with the cases described above.

An NTF process starts on the basis of previously defined trigger criteria. In the first step of the process, all relevant data from the OEM and the supplier are collected and analyzed and evaluated as part of the company's quality management. The goal of the process is to use new findings to lead to further investigations in the process or system. The NTF process, like complaints management, is part of a company's warranty management. Analysis results can be recorded, for example, in an 8D report or in an Ishikawa diagram.

The NTF process has an enormous relevance for a company, because a product that has no defects in the findings should not be disregarded. In particular, the defects that are not reproducible account for a large portion of warranty costs.

Under certain circumstances, a "No Trouble Found" verdict can have severe financial consequences for the manufacturer. The time, materials, and logistics costs involved in replacing the product are enormous and are not offset by any benefit or gain in knowledge. In addition, an NTF may suggest that the customer's problems have not been resolved, causing negative customer satisfaction and image damage. The NTF process is a clear requirement – firstly from the IATF and secondly from customers.