The No Trouble Found process, or NTF, is part of the defective part analysis process, which in turn contributes to the overall continuous improvement process (CIP). The term is mainly used in production industries, particularly in the automotive sector. Together with the appraisal, the No Trouble Found process constitutes the defective part analysis and is used to ensure that an error can always be identified, regardless of its category. The fault may be directly on the part, in the system or in the process.
The term “No Trouble Found” is based on the following situation: The user sends a product back to the manufacturer because a fault occurred with the product while it was in the user’s possession. The user expects the faulty product to be repaired or replaced. However, when the product is tested by the manufacturer, they cannot see any issues with the product; the device functions perfectly. It is therefore stated that there was “No Trouble Found”.
The No Trouble Found process can be executed, documented and therefore investigated precisely and straightforwardly within the scope of a CAPA process using a CAQ system. This process has huge significance for the company. This is because a product that does not show any faults during the appraisal should not simply be disregarded. Faults that cannot be reproduced, in particular, constitute a large proportion of a company’s warranty costs. A No Trouble Found can bring a huge financial burden on the manufacturer in certain circumstances. The time, expenditure of materials and logistics costs that exchanging a product brings with it are huge and do not provide any benefit or insights. In addition, an NTF means that the customer’s problem was not solved and therefore the customer is not satisfied and the company has lost points in terms of their image.
The VDA standard (German Association of the Automobile Industry e.V.) puts forth a methodical approach for the NTF process. This approach is to be used to handle cases like these.
An NTF process is triggered by the trigger criteria which have been set prior to the fault. In the first step of the process, all relevant data from the original equipment manufacturer and the supplier are collected and then analyzed and evaluated by the company’s quality management. The objective of the process is to spur new investigations on the process or on the system by obtaining new insights. The NTF process is part of complaints management within the company.