WARNING
READ “SAFETY INFORMATION” BEFORE USING THIS MANUAL.
This instrument is designed t o be used only qualified personnel who are (properly trained) skilled prof essional
automotive technicians.
It is assumed that the user has a thorough understanding of vehicle systems before using this instrument.
To use this instrument safely, it is essential that operating and servicing personnel follow both generally accepted
safety procedures and the safety precautions specified in this manual.
A DANGER identifies an imminently hazardous situation which, if not avoided, will result in death or serious injury to
the user or the bystanders.
A WARNING identifies conditions and actions that pose hazard(s) to the user or the bystanders.
A CAUTION identifies conditions and actions that may damage the instrument or the vehicle.
The term “Isolated (or Electrically floating)” is used in t his manual to indicate a measurement in which the COM
terminal of this instrument is connected to a voltage different from earth ground. The term “Grounded” is used when
the COM terminal is connected to an earth ground potential. The COM terminal of this instrument is rated up to 300
V rms above earth ground for the safety of isolated measurements.
Using Your Instrument Safely
Follow safe servicing practices as described in your vehicle service manual. To use this instrument safely, follow the
safety guidelines below :
DANGER
Use the instrument in service area WELL VENTILATED providing at least four change of air per hour. Engines
produce carbon monoxide, an odorless, colorless, and poisonous gas that causes slower action time and can
result in death or serious injury. Route exhaust outside while testing with engine running.
Set the parking brake and block the wheels, especially the wheels on front-wheel drive vehicles, before testing or
repairing the vehicle because the parking brake does not hold the drive wheels.
Be sure there is adequate clearance between any moving components when testing. Moving components and
belts can CATCH loose clothing, parts of your body or the instrument and cause serious damage or personal
injury.
Always wear approved safety eye protection when t esting or repairing vehicles. Objects can be propelled by
whirling engine components can cause serious injury.
When handling any signals higher than 150 V peak, don t electrically activate BOTH CH A and/or CH B
terminal(s) AND USB terminal together at a time. If they are electrically activated simultaneously, a death or a
serious personal injury could be resulted in.
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If you had a DSO, you could look at the output signal from each of the wheel speed sensors. From this you would
have discovered that the left rear wheel speed sensor had some very fast aberrations that caused the ABS computer
to act strange. You replace the left rear wheel speed sensor to cure the problem. The scan tools missed this problem
because no trouble codes were set and the computer communication bus was too slow to pick up the spikes. The
DMMs missed this problem because it averaged the sensor signals and could not see the fast abberations.
Scan tools and DMMs sample very slow when compared to DSOs. DSOs are typically more than a few hundred
thousand times faster than scan tools and more than 1,000 times faster than DMMs.
There are many examples of vehicle signals that DMMs and scan tools are unable to see. There are many vehicle
problems that can occur that really require a DSO or combination DSO and DMM to diagnose accurately.
1.2 VEHICLE SERVICE MANUALS
This inst rument tells how to hook up it to the selected vehicle components to be tested. However, it is strongly
recommended that you consult the manufacturer’s service manual for your vehicle before any t est or repair
procedures are performed in order to get the color of the wire or the PCM’s pin number from a wiring diagram.
For availability of these service manuals, contact your local car dealership, aut o part s store, or bookstore, The
following companies publish valuable repair manuals:
• Mitchell International
14145 Danielson Street
Poway, CA 92064
Tel : 888-724-6742
• Haynes Publications
861 Lawrence Drive
Newbury Park, CA 91320
Tel : 1-800-442-9637
• Motor Publications
5600 Crooks Road, Suite 200
Troy, MI 48098
Tel : 1-800-426-6867
• Helm Inc.
14310 Hamilton Avenue
Highland Park, MI 48203
Tel : 1-800-782-4356
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2. SAFETY INFORMATION
