Malfunction analysis using check list for interview

In order to identify the malfunction phenomenon correctly and make an appropriate decision, it is important not to introduce any bias into the troubleshooting process. In order to check the malfunction phenomenon, it is extremely important to ask the customer about the conditions when the malfunction occurred.
The following five items are valuable points in performing malfunction analysis. Sometimes, malfunction or repair history that seems not related to the current malfunction is useful. When performing troubleshooting, it is necessary to gather such information as much as possible and to correctly know how these troubles are related to the current one. Fill in each system diagnosis section of the check list for interview.
- What: Vehicle model, system name
- When: Date/Time, frequency
- Where: Route conditions
- Conditions: Driving conditions, weather
- What was happening when the malfunction occurred?: Malfunction phenomena
  NOTE: The following is a sample check list for interview.
  
  Fig 1: Engine Diagnosis Checklist
  Courtesy of SUBARU OF AMERICA, INC.