Page 92 - MODULE QUALITY TOOLS DMQ 30262

DMQ 30262

1. Problem Symptom is quantified and converted to “Object and Defect”
2. Problem Symptom is converted to Problem Statement using Repeated Whys

3. Possible and Potential Causes are collected using deductive tools (i.e. Fishbone or
Affinity Diagram)

4. Problem Statement is converted into Problem Description using Is / Is Not
5. Problem Description reduces the number of items on the deductive tool (from step 3)

6. Comparative Analysis between the Is and Is Not items (note changes and time)
7. Root Cause theories are developed from remaining possible causes on deductive tool

and coupled with changes from Is / Is Not
8. Compare theories with current data and develop experiments for Root Cause

Verification
9. Test and confirm the Root Causes

Is Is Not Example

Example: Multiple Why Technique

The Multiple / Repeated Why (Similar to 5 Why) is an inductive tool, which means facts are
required to proceed to a more detailed level. The steps required to determine problem

statement are:

1. Problem Symptom is defined as an Object and Defect i.e. “Passenger Injury”

2. Why? In every case “SUV’s Roll Over”

3. Why? In every case, it was preceded by a “Blown Tire”
4. Why? Many explanations may be applied, therefore the team cannot continue with
another repeated why past “Blown Tire”

5. Therefore, the Problem Statement is “Blown Tire”
6. Why? Low (Air) Pressure, Tire Defect (Degradation of an Interface) and High (Ambient)

Temperature
7. Counter measures assigned to low pressure and tire defect

This example uses only 4 of the 5 Whys to determine the root causes without going further into
the systemic reasons that supported the failure. The Repeated Why is one way to depict this

failure chain. Fault Tree Analysis (FTA) could also be used.

KKTM Kuantan 91 DMQ 30262