January 2, 2006

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5 Why Analysis

• January 2, 2006

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5-Why Training Agenda

• Where does 5-Why Fit within the PRR process
• Understanding of 5-Why
• Quick 5-Why Exercise as a group
• Critique Sheet
• 5- Why Examples
• Wrap Up/Discussion

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5-WHY
Where does it fit within the PRR process?

• After a supplier has submitted an initial
  response and containment plan (Step 2 in the
  PRR process), a detailed investigation is
  necessary to determine what caused the problem.
  Step 4 (Supplier determines the root cause)
  requires a 5-Why analysis to help in identifying
  the root cause of the problem.
• Going back to one of the elements within the
  Purpose of a PRR to facilitate problem
  resolution, 5-Why is the prescribed tool for
  determining the root cause of the problem to
  facilitate problem resolution.

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Why
Is the powerful question own it!!
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Power of Asking Questions
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Power of Asking Questions
Who are the best at asking questions to solve
problems?
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Power of Asking Questions
because they keep asking objective, open-ended
questions until the answer is simple and clear
When working with people to solve a problem, it
is not enough to tell them what the solution is.
They need to find out and understand the solution
for themselves. You help them do this by asking
open-ended , thought provoking questions.
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Close-Ended vs. Open-Ended Questions
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Benefits of Open-Ended Questions

• Requires thought
• Promotes additional research
• Enhances problem solving skills
• Does not assume there is one right answer
• Avoids predetermined answers
• Stimulates discussion
• Empowers the person answering

In many circumstances, it is not only the answer
itself, but the process by which the answer was
determined that is important when asking an
Open-Ended question
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More Examples
Example 1
Did the lack of a PM system cause this tool to
break? (Close-Ended question, can be answered by
a yes or no, gives the person a predetermined
answer that PM is to blame)
What could have caused the tool to
break? (Open-Ended, probing question forces the
person to think about all possibilities, not just
PM)
Example 2
Would improving material flow help reduce lead
times? (Good question but its still
Close-Ended, focuses the person on material flow
as a means to reduce lead time. Is this the best
improvement?)
What are some options on improving lead
time? (Open-Ended, triggering more thought and
research on all variables impacting lead time.)
Example 3
Is equipment capability causing the variation in
your process? (Close-Ended, can be answered by a
yes or no, focuses the person on equipment
being the source of variation)
What could potentially cause variation in your
process? (Open-Ended, triggering more thought
and research, opens up possibilities of variation
with man, material method, not just machine)
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5 Why Overview
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5-Why Analysis Three Paths

• 5-Why
• Specific problem
• Why did we have the problem?
• Problem not detected
• Why did the problem reach the Customer?
• System failure
• Why did our system allow it to occur?

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5-Why Analysis
Specific
Detection
Systemic
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Root Cause Analysis
Delco fuse box Insert example
What tool do We use for this?
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Brainstorming
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Grasp the Situation

• Part I Grasp the Situation
• Step 1 Identify the Problem
• In the first step of the process, you become
  aware of a problem that may be large, vague, or
  complicated. You have some information, but do
  not have detailed facts. Ask
• What do I know?
• Step 2 Clarify the Problem
• The next step in the process is to clarify the
  problem. To gain a more clear understanding,
  ask
• What is actually happening?
• What should be happening?
• Step 3 Break Down the Problem
• At this point, break the problem down into
  smaller, individual elements, if necessary.
• What else do I know about the problem?
• Are there other sub-problems?

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 Grasp the Situation

• Step 4 Locate the Point of Cause (PoC)
• Now, the focus is on locating the actual point of
  cause of the problem. You need to track back to
  see the point of cause first-hand. Ask
• Where do I need to go?
• What do I need to see?
• Who might have information about the problem?
• Step 5 Grasp the Tendency of the Problem
• To grasp the tendency of the problem, ask
• Who?
• Which?
• When?
• How often?
• How much?
• It is important to ask these questions before
  asking Why?

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5-Why Analysis

• Step 1 Problem Statement
• Is the problem statement clear accurate?
• Is the analysis on the problem as the customer
  sees it?
• Step 2 Three Paths
• Are all three legs filled in?
• Are there any leaps in logic?
• Can you ask one, two, or three more Whys?
• Is there a cause-and-effect relationship in each
  path?
• Can the problem be turned on and off?
• Does the path make sense when read in reverse?
• Do the whys relate to the actual error?
• Does the non-conformance path tie to design,
  operations, dimensional issues, etc.?
• Does the detection path tie to the customer,
  control plans, etc.?
• Does the systemic path tie to management issues
  or quality system failures?

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5-Why Analysis

• Step 3 Corrective Actions
• Is there a separate action for each root cause?
• Is it possible to implement each corrective
  action?
• Do corrective actions require Customer approval?
  If so, how will they be communicated to the
  Customer?
• Is there evidence to support verification of
  corrective actions?
• Are corrective actions irreversible?If not, do
  actions address ongoing containment?
• Is there a plan to standardize lessons learned
  across products, departments, etc?
• Step 4 Lessons Learned
• How could the problem have been foreseen?
• How will information be implemented?
• On the line or in the plant?
• At the point of detection?
• Cross functionally at the Supplier?
• Other products/plants?

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5-Why Analysis

• Step 5 Overall
• Are there gaps or holes?
• Are there things missed or not documented?
• Do corrective actions address actions the
  Supplier owns?
• How many iterations of 5 Why Analysis have there
  been?
• Who prepared the 5 Why Analysis?
• One person?
• Sales representative ?
• Clerk?
• The best answer is a cross functional team that
  understand the product and process!
•    

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Therefore Test
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5-Why Analysis
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• 5-Why Example
• (Non-conformance)

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5-Why Example - PPAP Submittal (Non-conformance)
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• 5-Why Example - PPAP Submittal
• (Detection)

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• 5-Why Example - Business Plan
• (Non-conformance)

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• 5-Why Example - Business Plan
• (Detection)

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  Flex Industries Case Study-Background

•  
• Jake Ryan is the Quality Manager at Flex
  Industries. Flex is a component supplier that
  manufactures metal stampings and light assembly
  products. The company has a reputation for
  supplying high quality parts on a consistent
  basis. Seldom has there been a customer
  complaint. Flex has Quality representatives
  called Customer Support Engineers (CSEs) at
  every customer assembly plant. The CSEs report
  any problems to Jake for investigation and
  follow-up.
•  
• At 700 a.m. this morning, Jake received a call
  from Janet, CSE at the Winding River Assembly
  Plant. Janet informed him that the customer had
  found five defective stabilizing brackets on
  second shift last night. She checked the
  remaining inventory and there were no defects in
  the remaining 326 pieces. The manufacturing
  sticker on the back of the brackets indicated
  that they were made by the second shift operator.
  Normally, the stabilizing bracket is fastened to
  the regulator motor with three rivets. The five
  defective brackets had only two rivets in them.
  The lower set of rivets on all five brackets was
  missing a rivet. This was the first time that
  the problem occurred.

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Background

• GOOD BAD
•  
•  

Jake set-up containment procedures at the plant
warehouse to sort for discrepant materials. As
of this morning, two more defective brackets had
been found in the remaining 2019 pieces of
inventory at Flex.
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Cause Investigation

• Jake went out to the floor to talk with the team
  leader of the two rivet lines (East and West) and
  the area quality assurance auditor. He informed
  Sam (the team leader) of the quality problem and
  asked him to identify the line which runs the
  stabilizing bracket assembly. Sam directed Jake
  to the East line which runs Winding River
  assembly brackets only.
• At the East Line, he spoke with Judy (the QA
  Auditor for the area) and asked to see the
  quality log sheets. Jake and Judy reviewed the
  Nov. 11th log sheet and could not find anything
  out of the ordinary. He asked her to set-up
  in-house containment procedures to sort for any
  discrepant material in the finished goods area.
• Next, Jake tried to locate the second shift
  operator whose clock number was on the defective
  parts. Since that operator was gone, Jake spoke
  with the current machine operator (Ben). He
  asked Ben about any recent difficulties with the
  rivet machine. Ben said that he hadnt noticed
  anything out of the ordinary. Ben also
  mentioned, however, that there had never been any
  quality bulletins posted in the two years that
  this particular part has been running.
• Jake decided to stay in the area to watch the
  machine run for a while. After about 15 minutes,
  he watched Ben dump rivets into the feeder bowl
  to prepare for the next run.

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Cause Investigation

• Shortly after restarting rivet operations, Ben
  walked over to another riveter and came back with
  a steel rod. Ben poked around the rivet chute
  and then continued working. Jake approached Ben
  and asked him about the steel rod. Ben replied
  that from time to time the chute gets jammed and
  he has to clear it out. This happens two or
  three times during a shift. He didnt mention
  this in his earlier conversation with Jake
  because the problem has existed ever since he
  started working with this machine. The previous
  operator showed him how to clear the chute. All
  the rivet machines are like this.
• Jake called the Machine Repair Department and
  asked that someone look at the rivet track. A
  slight gap in the track was found and removed,
  and Ben continued to work.
• Two hours later, Jake got a call from Ben saying
  that the track was still jamming. As far as Jake
  could see, only rivets were in the bowl. Next,
  Jake looked into the rivet supplier containers.
  There was some foreign material in the blue
  container, but none in the red container. The
  label on the blue container showed that it was
  from Ajax Rivet, Inc., and the label on the red
  container indicated that it was from Franks
  Fasteners. Obviously, the foreign material was
  entering the rivet feeder bowl and jamming the
  track.

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Cause Investigation

• Jake called Maintenance and requested that the
  bowl be cleaned. He also added the cleaning
  operation to the preventive maintenance schedule
  on the equipment. He then called both Ajax
  Rivet, Inc. and Franks Fasteners. He asked
  about the cleaning procedures on the returnable
  containers. Franks did a full container purge
  and clean. Ajax just re-introduced the
  containers back into their system. When Jake
  asked why Ajax did not clean their containers, he
  was told that Ajax was not aware that such a
  policy was needed.
• Upon further investigation, Jake learned that
  Franks Fasteners supplies other major automotive
  companies. Since these companies require that
  all returnable containers be cleaned, Franks
  instituted the purge as part of its practice for
  all customers. Ajax Rivet, however, depends
  primarily on Flex as its major customer. No such
  policy has ever been required of them.

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Cause Investigation

• Jake called the Material Control Department and
  requested that a container maintenance policy be
  drafted which would apply to all their suppliers.
  He also asked that a machine modification be
  developed to sense for the presence of rivets.
  Hopefully, this would error-roof the process.
• Key Players
• Jake Quality Manager
• Janet CSE, Winding River Plant
• Sam Team Leader, East Line
• Judy QA Auditor, East Line
• Ben Machine Operator

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Generic Information for 5-Why Example Regular
Cola Soft Drink vs. Diet Cola

• The plant received a PR/R from a customer. (We
  use 5-Why Analysis to answer every PR/R.)
• The PR/R states that the customer received
  Regular Cola in the right container (same for
  both products) with the Diet Cola label. The
  order called for Regular Cola.
• The plant has two identical lines that are
  capable of running either of our two products.
  The lines are located immediately beside each
  other. The only differences in the products are
  the syrup and the labels.
• The plant runs both lines 24 hours per day.
  There are three shifts that run 700 a.m. to 300
  p.m., 300 p.m. to 1100 p.m., and 1100 p.m. to
  700 a.m.
• The date code indicates that the defective
  product was manufactured at 303 p.m.
• Defective product has been contained and sorted.

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Bottling Process Flow for 5-Why
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Generic Information for 5-Why Real Example O
Ring Seal

• The plant received a PR/R from a customer. (We
  use 5-Why Analysis to answer every PR/R.)
• The PR/R states that the customer received
  Mixed/Foreign Material in Shipment.
• The supplied part is an O Ring seal for oil
  filter.
• A cutting operation produces the part to
  specified size. As the raw material (cylindrical
  component) goes through the cutting operation,
  the irregular end-cuts are removed from the
  station.

• Cutting Station

• Matl Flow

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Is this a good or bad Non-Conformance leg?
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Is this a good or bad Detection leg?
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A good 5-Why will answer Yes to the five PDCA
questions
A problem well defined is a problem half solved
PLAN
ACT
Understand the problem
Standardize
1. Is the problem statement CLEAR and
ACCURATE? 2. Has the SYSTEMIC root cause(s)
been identified for all legs?
5. Has a plan been identified to STANDARDIZE and
take all lessons learned across products,
processes, plants, functional areas, etc.?
DO
CHECK
Execute the Plan
Follow-up
3. Has IRREVERSIBLE CORRECTIVE ACTION(s) been
implemented for ALL root causes?
4. Has a plan been identified to verify
the EFFECTIVENESS of all corrective actions?
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Is this a good Corrective Action plan?
Corrective Action w/ Responsibility
Date
Plan
Fastener P/N 10001 would not assemble
A
Do
1. Replace worn tool (K. Jones)
6/1/03
Burrs on the thread
2. Begin conducting PM on all dies after
every run, minimum 1 x / day, to collect
history (L. Burg)
6/1/03
Do/Act
Worn stamping tool
3. Assess adjust PM intervals for all dies
based on history mfg recommendations
(B. Clark)
7/31/03
Do/Act
Tool exceeded recommended wear life
PM interval not adequate
Plan
PM failure No system to strategically set PM
intervals
A
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5-Why Critique Sheet

• General Guidelines A.) Dont jump to
  conclusions! B.) Be absolutely objective. C.)
  Dont assume the answer is obvious. D.) If you
  are not thoroughly familiar with the process
  yourself, assemble a cross-functional team to
  complete the analysis.
• Step 1 Problem Statement
• Is the analysis being reported on the problem as
  the Customer sees it?
• Step 2 Three Paths (Dimensional, Detection,
  Systemic)
• -Are there any leaps in logic?
• -Is this as far as the Whys lead? Can you still
  ask one, two, three more whys)?
• -Is there a true cause-and-effect path from
  beginning to end of each path? Is there
  statistical data/evidence to prove it? ---Can the
  problem be turned off and on?
• -Does the path make sense when read in reverse
  from cause to cause? (e.g.We did this, so this
  happened, so this happened, and so on, which
  resulted in the original problem.)
• -Do the whys go back to the actual error?
• -Does the systemic path tie back to management
  systems/issues?
• -Does the nonconformance path ties back to
  issues such as design, operational, tiered
  supplier management, etc?
• -Does the detection path ties back to issues
  such as protect the customer, control plans,
  etc?

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5-Why Critique Sheet (cont)

• Step 3 Corrective Actions
• -Does each corrective action address the root
  cause from a path?
• -Is there a separate corrective action for each
  root cause? If not, does it make sense that the
  corrective action applies to more than one root
  cause?
• -Is each corrective action possible to
  implement?
• -Are there corrective actions that affect the
  Customer or require customer approval? How will
  they be communicated to the Customer?
• -Is there evidence and documentation to support
  the validity of the corrective actions?
• -Are the corrective actions irreversible? If
  not, are there corrective actions in place that
  address containment?
• Step 4 Lessons Learned
• -How could this problem have been foreseen?
• -How will this information be implemented
• a.) on the line or in the plant?
• b.) at the point of detection?
• c.) cross-functionally at the Supplier?
• d.) other product/plants?
• -Are there lessons learned for the Customer?
• Step 5 Overall
• -Do there seem to be big holes where ideas,
  causes,
• corrective actions, or lessons learned are being
  avoided?
• -Where things are missed or not documented?

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5-Why Analysis Cola Example Path A
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5-Why Analysis Cola Example Path B
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5-Why Analysis Cola Example Path C
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5-Why Analysis ORing Example Path A
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5-Why Analysis ORing Example Path B
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5-Why Analysis ORing Example Path C
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Problem Case Audit Standards

• 5-Why Analysis Green, Yellow, Red
• G Can follow logic and flow of all 3 legs of 5
  why's. The legs all differentiate "What is the
  problem, why wasn't it detected, and what
  happened systemically."
• Y All 3 legs filled out, some leaps of logic,
  needs minor corrections to improve.
• R 1 or 2 legs missing, Leg 1 repeated as leg 2
  or 3, not understanding what the different legs
  mean--typically missing what the systemic leg is.
  Poor answers on 2 or more legs.