Important Points in the Customer Problem Analysis
What ––––– Vehicle model, system name
When ––––– Date, time, occurrence frequency
Where ––––– Road conditions
Under what conditions? ––––– Running conditions, driving conditions, weather conditions
How did it happen? ––––– Problem symptoms
(Sample) Supplemental restraint system check sheet.
Supplemental Restraint System Check Sheet
Customer’s Name
Date Vehicle Brought In
Registration No.
Frame No.
Odometer Reading
km
miles
Date Problem First Occurred
Weather
Temperature
Vehicle OperationFine Cloudy
StartingIdling
Driving
Constant speed Acceleration
OtherInspector’s
Name
CUSTOMER PROBLEM ANALYSIS CHECK
Registration Year
RainySnowyOther / / / /
/ /
Approx.
Deceleration [
]
IN–20– INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1. CUSTOMER PROBLEM ANALYSIS
In troubleshooting, the problem symptoms must be confirmed accurately and all preconceptions must be
cleared away in order to give an accurate judgement. To ascertain just what the problem symptoms are, it
is extremely important to ask the customer about the problem and the conditions at the time it occurred.
Important Point in the Problem Analysis:
The following 5 items are important points in the problem analysis. Past problems which are thought to be
unrelated and the repair history, etc. may also help in some cases, so as much information as possible should
be gathered and its relationship with the problem symptoms should be correctly ascertained for reference
in troubleshooting. A customer problem analysis table is provided in DI section for each system for your use.
BE199–02
I01273
1
2 3
BE–6
– BODY ELECTRICALCOMBINATION METER
INSPECTION
1. INSPECT SPEEDOMETER ON–VEHICLE
Using a speedometer tester, inspect the speedometer for allow-
able indication error and check the operation of the odometer.
HINT:
Tire wear and tire over or under inflation will increase the indica-
tion error.
Europe Models
(mph)(km/h)
Standard indication Allowable range Standard indication Allowable range
20 20 – 24.5 20 20 – 26
40 40 – 46.5 40 40 – 48
60 60 – 68.5 60 60 – 70
80 80 – 90.5 80 80 – 92
100 100 – 112.5 100 100 – 114
120 120 – 136
140 140 – 158
160 160 – 180
If error is excessive, replace the speedometer.
2. INSPECT VEHICLE SPEED SENSOR OPERATION
(a) Connect the positive (+) lead from battery to terminal 1
and negative (–) lead to terminal 2.
(b) Connect the positive (+) lead from tester to terminal 3 and
the negative (–) lead to terminal 2.
(c) Rotate the shaft.
(d) Check that the voltage changes from approx. 0 V to 11 V
or more between terminals 2 and 3.
HINT:
The voltage changes be 4 times every revolution of the speed
sensor shaft.
If operation is not as specified, replace the sensor.
3. INSPECT TACHOMETER/
ON–VEHICLE
(a) Connect a tune–up test tachometer, and start the engine.
NOTICE:
Reversing the connection of the tachometer will dam-
age the transistors and diodes inside.
When removing or installing the tachometer, be care-
ful not to drop or subject it to heavy shocks.
