ADVANCED TECHNICIANS COURSE THE BASICS.ppt

ADVANCED TECHNICIANS COURSE THE BASICS

1. ADVANCED
TECHNICIAN'S COURSE
THE BASICS OF TROUBLE DIAGNOSIS
OVERSEAS SERVICE DEPARTMENT
HINO MOTORS, LTD

2. 1. THE BASICS OF TROUBLE DIGNOSIS
1) To diagnose trouble
(2) Work efficiently and narrow down possible causes
until you reach the real causes.
(1) Have a clear grasp of the trouble symptoms.

3. 2) Trouble diagnostic method Diagnostic method Features
New mechanic Checks one part at a time
and compares it with a
standard.
Trouble can be diagnosed if values are
stipulated by inspection standards, but
all related parts must also be checked.

The number of inspection points is
excessive and time is required for
diagnosis.
The real causes cannot be
discovered, so cases are often
accompanied by trouble.
Veteran mechanic Presumes causes backed
up by sound theories, and
takes a focused approach
to inspection.
Accurate work can be done promptly,
without performing unnecessary work.


Systematic trouble diagnosis

4. 3) The importance of theory and practice
WHY?
Following up each and every cause-and-effect relationship

5. 5 steps of the procedure for diagnosing trouble
2. TROUBLE DIAGNOSTIC PROCEDURE
1ST STEP
CONFIRMING AND
REPRODUCING
PHENOMENA
2ND STEP
DETERMINING
THE EXISTENCE
OF TROUBLE
3RD STEP
PRESUMING THE
CAUSES OF
TROUBLE
4TH STEP
CHECKING
PRESUMPTIONS AND
DISCOVERING CAUSES
5TH STEP
PREVENTING
RECURRENCE
OF TROUBLE

6. Step 1Confirming and reproducing phenomena
Listen to details regarding
phenomena from the customer.
The phenomena indicated by
the customer are reproduced
when the vehicle is brought
into the service shop.
The phenomena indicated by the
customer are not reproduced
when the vehicle is brought into
the service shop.
Asking questions
Have a correct view
of the facts
Reproduce phenomena
according to questions
asked.
Have a correct view
of the facts
Asking questions
Asking the customer about the conditions
surrounding the occurrence of trouble, in
order to reproduce the phenomena.
(1) What: What are the phenomena?
(2) When: When did they occur and how
frequently?
(3) Where: Where did they occur and
what were the road conditions?
(4) Under what conditions: What were
the driving conditions?
(5) What happened: How were the
phenomena experienced?

7. Step 2Determining the existence of trouble
Just as there are many types of customers, there are many types of
complaints brought into a Hino workshop.
Not all of them, however, indicate the existence of trouble.
Accepting repair work that is unnecessary is not only a
waste of time, it also results in loss of trust on the part of
the customer.
Confirming and
reproducing phenomena
No trouble Trouble
Handle from standpoint
other than trouble.
Proceed to Step 3 and
subsequent work
Trouble (breakdown)
Something is wrong with a part of the
machine and function has been lost.
Step 1

8. Step 3Presuming the causes of trouble
Determining existence
of trouble
Step 2
Narrow down causes to individual parts,
considering the function, structure, and
operation of each system.
Narrow down causes to each system,
considering the functions required by
the vehicle.
Presuming causes
of trouble
(3)Past history
(4)Experience
(1)Structure and
operation
(2)Use conditions
(1)Did the occasions on which trouble occurred have any common conditions?
(2)Are the customer's driving habits affecting the operation of the vehicle?
(3) Can the causes of trouble be found in the vehicle's past service history?
(4)Were there any similar repairs made in the past?
To search for the causes of trouble more accurately

9. Step 4Checking presumptions and discovering causes
Step 3
Presuming causes of trouble
Checking presumptions
Discovering causes
Inspection work points:
(1) Systematically check the vehicle function, structure,
and operation.
(2)Check each system, gradually narrowing down the
focus of the inspection to individual parts.
(3) Whenever possible, use a tester for the inspection.
(Measured values are materials for objective
decisions.)

10. Step 5Preventing recurrence of trouble
The repair will be initially completed not only when the problem
has been solved but also when there is no fear that it will recur.
Step 4
Checking presumptions and
discovering causes
Tracking the factors of trouble
occurrence
Discovering the real
causes
Recurrence prevention points:
(1)Determine if the trouble is an independentoccurrence
or if its cause originates in another part.
(2)Determine if the trouble is due to life characteristics.
(3)Determine if the trouble is due to faulty serviceor
maintenance.
(4)Determine if the trouble is due to improper operation or
driving method.
(5)Determine if trouble is due to unsuitable use conditions.

11. Grasping facts by asking questions
(1) Content that must be grasped
Listening to customer's description of
phenomena
(What is wrong and how is it wrong)
Determine the causes from
the presumed work content
and consult with the customer
when the vehicle is returned to
the customer.
•Confirming customer's needs
and requirements
(Example):
Reproducing the phenomena without
having to test drive the vehicle.
Reproducing the phenomena indicated
by the customer when the vehicle is
brought into the service shop
=

12. Having to test drive the vehicle in
order to reproduce the phenomena.
Not reproducing the phenomena indicated
by the customer when the vehicle is
brought into the service shop
=
•Items required to reproduce phenomenaSince when? When trouble occurred
On what occasions?
At startup, laden or unladen, after driving
OOkm, etc.
In what locations?
Climbing a hill, tight curve, highway conditions,
etc.
As a result of what action?
When brakes are applied forcefully, when
rapidly accelerating, etc.
Frequency of occurrenceEvery day, once a week, once a month, etc.

13. (2) Additional required informationItem How to utilize information
Period when trouble occurred for the
first time
As prior knowledge for presuming causes of
trouble
Past service history and maintenance
As prior knowledge for presuming causes of
trouble
Where are periodic inspection and
maintenance performed?
As prior knowledge for determining suitability
of service or for presuming causes of trouble
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