The document outlines the steps in a 5-Why report used to analyze product defects and determine their root causes. The steps include: 1) conducting an occurrence investigation; 2) analyzing the investigation to identify root causes using a 4M (man, machine, material, method) approach; 3) developing countermeasures to address the root causes; 4) evaluating the effectiveness of the countermeasures; and 5) horizontally deploying the improvements across other relevant operations. The goal is to identify and address root causes in order to prevent future recurrences of defects.

1. Contents of 5-Why Report : 1) Occurrence Investigation 2) Analysis on investigation (find out root cause) 3) Countermeasure 4) Evaluation on effectiveness 5) Horizontal deployment Whyyyyy…. until ROOT CAUSE is defined, then countermeasure it, hence avoid REOCCURENCE 5-Why Report

2. Occurrence Investigation ( single or more than two, production Lot., position, value, influence to vehicle) 1. Rejected quantity, Rejected ratio 2. Rejected frequency ( continuously, seldom ) 3. Condition of occurrence ( how to founded out. , detail of rejects ) 4. Lot No. of products, Serial No. of products 5. Area of country ( one area, more than one area ) 6. Term of used 5-Why Report To Collect all Relevant Information

3. Analysis on Investigation ( 4M, Recurrence test, level of investigation, measurable ) 1. Detail investigation to actual rejected products 2. Production and evaluation condition when defective products was produced, 3. Recurrence test & estimation of rejects quantity and frequency 4. Comparison of actual operation procedure and rule 5. 4M investigation to defective products manufacturing 5-Why Report Root Causes

4. Analysis on Investigation Man Identification of operator, Education detail, Evaluation of level, Detail of management Evaluation of training result Machine Identification of trouble, Evaluation of process capability, Checking of data when defects was produced ( bias ), M/C maintenance schedule and result, Recurrence trial, Estimation of occurrence frequency, Rule of daily setup and record Method Evaluation of rule which is related defective products occurrence, Possibility of defects when operator follows rule, System of rule fixing, Responsibility to the rule 1) Education of rule 2)Record of operation 3)Presence of check sheet 4)Evaluation of training effectiveness 5)Level of rule ( assurance degree ) 6)Management job documentation Material Any change of materials, production Lot., Evaluation to the material specification, Dimensional confirmation of rejected products 5-Why Report Details Analysis on 4M

5. Countermeasure ( 4M, Management, Systematizing, Assurance degree, Measurable ) 1. Countermeasure to the 4M 2. Written rule of countermeasure 3. Evaluation of countermeasure ( Effectiveness of recurrence and outflow prevention to the trouble until three level root cause ) 4. Improvement of management job 5. It is not accepted that training is only one countermeasure, Improvement of system is required. 6. Countermeasure are required to the cause of occurrence and the cause of outflow The cause of occurrence is to the station of defected products produced The cause of outflow is to the after process of production and management 7. Measurable countermeasure 8. Introduction of POKAYOKE 5-Why Report Countermeasure on the Root Causes so as to Prevent Reoccurrence

6. Effectiveness of Countermeasure ( 100% application of rule, Zero defect occurrence ) 1. Rejects occurrence after one month from countermeasure introduction 2. Condition of rule application ( record, operation method, management, job understanding level of operator ) 3. Revising of related documentation 4. Extracting of more improvement required process 5-Why Report Monitor, Amendment and Standardization

7. Horizontal deployment ( deployment as wide as possible, priority to the current production model and developing items ) 1. Similar model 2. Similar parts 3. Similar process 4. Operator training 5. Management job 6. The other fronts 7. Revising of related rule 8. Detail explanation in plant meeting 5-Why Report Extend the Improvement to Other Operations

8. 1. Deep digging to concentrated important area (4M). 2. Never do the personality 3. System approach ( early stage of rule making and management area ) 4. Evaluate and select the fact in each steps ( most influence items ) Points to be Noted on 5-Why ( Important condition in each steps ) Be Objective