Definition and Purpose
Service FMEA helps eliminate product failures due to improper installation, operation, maintenance and repair. For example, premature wear on an automobile tire is a potential failure mode which occurs if the tire is not maintained at the correct pressure. A service FMEA is a structured procedure for identifying and preventing service-related product failures, i.e., failures due to improper installation, operation, maintenance, or repair. For example, excessive wear on an automobile tire that is not maintained at the proper pressure.
The purpose of a service FMEA is to ensure that:
- Service tools will perform as required
- All necessary instructions are provided
- Instructions are clear and cannot be misunderstood
- Individuals who provide the service understand their responsibilities and know how to install, operate, maintain, and repair the product.
A service FMEA uses the same form as the design FMEA. The service FMEA is initiated and drafted by a service engineer.
The review team usually consists of the:
- Product design engineer
- Manufacturing engineer
- Various service personnel
Benefits
- The customer experiences fewer failures throughout the life cycle of the product.
- The reputation of the product improves, which leads to increased sales.
- Warranty costs are reduced.
- The service FMEA helps ensure that the design intent of the product is carried out in the field.
Basic Steps
Draft Stage
- For a service tool, the service engineer begins drafting an FMEA form based on input from the design and manufacturing engineers, as well as service personnel. The same issues are addressed as in a design FMEA:
- Function: What exactly is the tool expected to do?
- Failure mode: How could the tool fail to perform its function?
- Effect: What effect would the failure mode have on the end user and on the product?
- Cause: What could cause the tool to fail?
- Prevention or detection: How can the cause of the failure mode be prevented or detected?
- For a service manual, the engineer does not use an FMEA form, but proceeds to draft the manual itself, based on the product drawing, spec sheet, test results, and information supplied by the design engineer.
Team review stage
- The draft FMEA form is distributed to team members for review. They add:
- Severity ranking
- Likelihood ranking
- Effectiveness ranking
- Failure modes, effects, preventions and detections which may have been overlooked
- The service engineer adds the team's comments and rankings to the original draft to create a composite FMEA form.
- A Risk Priority Number is calculated for each potential failure mode.
- The service manual is also circulated to team members to ensure that all instructions and drawings are accurate and complete.
- A field test may be conducted in which typical mechanics are asked to perform the service based on instructions in the manual.
- This helps ensure that no information is missing, out of sequence, or likely to be misinterpreted with dangerous consequences.
- The results of the field test are documented and included with the rest of the FMEA.
Implementation stage
- Corrective actions, if warranted by the Risk Priority Numbers, are implemented and the tool design is released to manufacturing.
- The manual is revised based on the reviewers' corrections and the results of the field test, then sent to print.