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Transcript
H e e e e r e ’ s . . . Testy!
The goal of this new series of articles is to give
meter, and a whole lot more. The Mastertech uses
you a foundation to evaluate high tech equipment,
an assortment of interchangeable software
such as lab scopes. We’ll build this foundation in
cartridges, which adapt the tool to specific tasks
several different ways. We’ll interview the people
and specific vehicle manufacturers.
directly involved with the development of the
Vetronix has announced that its OEM-validated,
equipment and learn the strategies that
dealer-level diagnostic software for
guided that develop-
Honda, Toyota, Suzuki and Kia applica-
ment. We’ll provide
tions is now available to the aftermarket.
you with information
Vetronix claims that over 40 percent of
about the specific capa-
new vehicles manufactured world-
bilities of each piece of
wide are serviced at the dealer level
equipment. And whenev-
with diagnostic products it has
er possible, we intend to
developed. Through agreements
actually use each piece of
reached with OEMs, the company
equipment in a shop situa-
is now able to offer ScanTest
tion so we can properly eval-
Software for Honda/Acura, Toyota/Lexus, Suzuki
uate its real-world capabilities.
and Kia vehicles to the aftermarket. All four soft-
Our first installment features the Vetronix
ware programs run on the Vetronix Mastertech.
Mastertech, a combination scanner/scope/digital
The Test Bench
Q&A
We submitted a series of questions to the
folks at Vetronix, to learn more about their
company, and to learn more about the
Mastertech in particular. While we don’t
have room to print all of the questions and
answers, we’ll try to hit the highlights (concentrating
primarily on the scope features). We may be able to
print the complete transcript in another forum at a
later date. Stay tuned as this series develops.
IS: How would you describe the Mastertech?
Vetronix: The Mastertech is referred to as the MultiFunction Tool or MFT. It provides the technician
8
with a full-function bidirectional control
Scantool, Automotive Oscilloscope and
Digital Meter. This equips the technician
with most of the tools needed to diagnose
vehicle On-Board computer failures in a single package. The Mastertech’s Tech Tool Box provides additional functions like a stop watch and
count down timer. These can be used for various
controlled tests, such as measuring injector flow or
determining how long a vehicle takes to come out of
open loop. Along with the timer functions, math
functions such as basic electronic formulas, metric
to American conversion formulas and a calculator
are also available.
February 1998
IS: What accessories are available for the Mastertech?
Vetronix: The basic Mastertech kit comes with MFT
Software, OBD II compatibility, a Diagnostic Lead
Set for the Oscilloscope functions, operator’s manual, DLC cable, power cord and AC/DC power supply.
It also comes with a waveform library—the
Waveform Assistant—which contains known good
automotive sensor waveforms. Special Mastertech
kit configurations are available to meet specific technician needs. The accessories listed below are available separately or are provided in specific
Mastertech kits:
• Scantest Software for GM, Ford, Chrysler:
Domestic Scantool software supports coverage up to
1998 model year.
• Toyota, Honda, Suzuki and Kia OEM software:
The same software used in the dealerships with
bidirectional controls covering multiple vehicles
systems such as Powertrain (engine and transmission), Body and Chassis.
• Software that provides reprogramming capability
for GM engine controllers.
• Enhanced Diagnostic Lead Set (EDLS): Provides
high voltage measurement of automotive signals and
ignition waveforms.
• TechView for Windows: Windows software that
allows the user to view real-time or Snapshot data
from Vetronix testers on a PC screen and store snapshots on a PC hard disk.
• The Vetronix PXA-1000 4 or 5- gas analyzer may
be interfaced with the Mastertech for control and
display of emissions readings.
• VP-411 Printer, a graphic serial printer that interfaces to Vetronix products.
IS: Is PC software available? If so, what enhancements does it offer?
Vetronix: TechView for Windows allows the user to
view and store vehicle data collected from Vetronix
testers, on a Windows 3.X or Windows 95 PC. Data
can be presented in many large display modes,
including Bar and Line graph modes.
IS: Can data and screens be printed out?
Vetronix: Yes, the Vetronix VP-411 serial graphic
printer can be used to print screen and text.
Standard text-based serial printer can also be used
for printing text only.
IS: Can the Mastertech be updated? If so, how?
Vetronix: The Mastertech platform was designed to
be easily updated by installing a new MFT Program
card programmed with new software. Scantest
February 1998
(scantool) software can be updated by replacing a
cartridge.
IS: What about the scope’s capabilities? Is it a fully
functional scope with all the expected features?
Vetronix: Yes, the Mastertech has a fully functional
automotive oscilloscope. The Mastertech was initially designed as a scantool with analog input capabilities. The oscilloscope and meter capabilities
were added to provide the technician with the ability to view automotive electronic signals while performing on-board vehicle control system diagnostics
for OEM vehicles (Toyota and Honda). A significant
advantage a Mastertech user has is that the unit can
be easily upgraded. Features, functions and capabilities can be easily added by changing Program Card
software or adding hardware modules, probes and
transducers.
IS: Another topic of major concern is a scope’s ability to capture glitches. What Mastertech features or
techniques do you suggest using for glitch capture?
Vetronix: Because the vehicle’s on-board computer’s
input circuits vary between sensor inputs the definition of a ‘high frequency abnormal signal’ may also
vary between sensors. With vehicle controller(s)
sampling components at different rates, it is important to only detect an anomaly or glitch that would
be detected by the vehicle controller. A nonadjustable glitch capture function can be misleading. Misdiagnosis and replacement of good components could result from the detection of a narrow
glitch that would never be detected by a vehicle controller. Our oscilloscopes provide the user with the
flexibility to customize the tester to display and
record the signals that could potentially be ‘seen’ by
vehicle powertrain controllers. When using the
Enhanced Diagnostic Lead Set (EDLS), an optional
accessory, in conjunction with the Mastertech or
PXA-1100, the component in question is selected
from a menu. The oscilloscope is automatically configured for that component selecting the appropriate
sampling rate. The proper sampling rate is crucial to
detecting an anomaly that would effect vehicle operation. Below is a list of functions of the Mastertech
and PXA-1100 oscilloscope that can be used for capturing abnormal signals and providing an adjustable
volt and time per division:
Single Shot: The oscilloscope can record a voltage
signal from the tester input based on the trigger voltage and edge trigger setup defined by the user. If
used properly, the technician can capture a ‘glitch’
or ‘high frequency abnormal signal’ custom to each
circuit or electronic system under test regardless of
screen refresh or time per division setting.
9
H e e e e r e ’ s . . . Testy!
Adjustable Trigger Level: Allows the user to set the
oscilloscope’s input trigger voltage level for Single
Shot function or regular display modes.
Edge Trigger Adjustment: Allows the user to set the
oscilloscope input to trigger off of a rising or falling
voltage signal for Single Shot function or regular
oscilloscope display modes.
all of the data because it is limited to only 160 pixels. The zoom function allows the user to zoom in
and view the data captured that was not displayed
in the previous screen. This may be significant in
locating a potential ‘glitch’ or anomaly in the signal.
IS: How many waveforms can I save and recall?
Vetronix: Four.
Adjustable Time Per Division: The adjustable time
scale of the oscilloscope displays voltage from the
input channel(s) on a display grid with 10 horizontal divisions ranging from 200 microseconds to 20
seconds per division.
Adjustable Volts Per Division: The adjustable volt
scale of the oscilloscope displays voltage from the
input channel on a display grid with 8 vertical divisions ranging from 0.1 volts to 5 volts per division.
(note: with the EDLS, 0.1 volts to 100 volts per division).
IS: Can it view secondary ignition signals?
Vetronix: Yes, when using the Enhanced Diagnostic
Lead Set (EDLS) the user can view primary and secondary ignition patterns along with high voltage,
automotive inputs over ±20 volts.
IS: Is a library of waveforms included?
Vetronix: Yes, the Mastertech software includes 35
known-good automotive sensor and ignition waveforms. It is referred to as the Waveform Assistant.
The library covers sensors including analog and digital MAF signals, Hall-effect or analog crankshaft
position sensors and upstream/downstream O2 sensor signals.
IS: What about waveform analysis? Are there cursors?
Vetronix: The oscilloscope comes with built- in utilities that allow the user to analyze a given signal.
The Mastertech has two cursors, with measurement
of the frequency of the time-period between the two
cursors. A Zoom function allows the user to zoom in
on a captured waveform.
IS: Many techs report that when they connect the
Mastertech to primary ignition the engine dies. I
have explained what is going on with this many
times. Many seem to think this is an issue with the
meters input impedance. Would you explain and
put this issue to rest?
Vetronix: Without requiring special probes, the
Mastertech can measure 0 ±20 volts. To read a signal
greater than ±20 volts, the Enhanced Diagnostic
Lead Set (EDLS) is required. This device scales
down the signal so that it can be read by the
Mastertech. The Mastertech also has voltage protection circuitry built into the analog input channels to
protect the unit damaging voltage spikes.
When the Mastertech’s oscilloscope input channel
is connected to a primary ignition circuit, with out
using the EDLS, the tester’s protection circuit will
‘clip’ the primary side of the ignition coil’s inductive ‘kick’ used to induce the firing voltage in the
ignition coil’s secondary circuit. This causes the
ignition coil to either not fire or the output would be
too low to fire the sparkplugs.
Always refer to the manual for proper use or if you
have any questions about the operation of the
Mastertech. Customer Support will answer questions that may not be answered in the manual.
IS: So, it is not the scope’s input impedance that
kills the ignition, it is the scope’s voltage protection
circuit kicking in. And according to your specs the
scope has a minimum of 1 megohm input impedance depending on the function selected. This situation shows how important it is to understand your
equipment and to read the manual.
IS: What is the MSRP?
IS: With some scopes it can be hard to tell if the
screen is actually updating. How does the
Mastertech indicate a ‘live’ waveform?
Vetronix: There is an indicator light located along
the screen base indicating a trigger.
Vetronix: It would be difficult to quote an MSRP
because the Mastertech can be purchased in many
different configurations. Call (800) 321-4889 for further information on pricing or to contact Vetronix
sales representative. You may also Circle No. 200 on
the Reader Service Card for further information.
IS: Explain the function of the ZOOM feature.
—By Jorge Menchu
Vetronix: The Mastertech oscilloscope will oversample a signal, however it may not be able to display
February 1998
11
H e e e e r e ’ s . . . Testy!
The Mastertech can be customized for a variety of uses. The tool
changes, based upon the cartridges that are inserted into its two
ports, or the specialized leads that are attached. Of most interest to import technicians are the manufacturer-specific cartridges available for the Mastertech. These give aftermarket
technicians access to the same diagnostic information available
to Honda/Acura, Toyota/Lexus, Kia, and Suzuki dealer techs.
Each cartridge adapts the Mastertech for specific tests.
The large keypad is the Mastertech’s most noticeable feature.
All of the tool’s menus can be easily navigated using the keys
arrayed at the top of the unit (arrow, yes, no, and enter keys).
All diagnostic lead connections, as well as communications ports
for printer, computer, and other Vetronix equipment, all located
along the bottom edge of the tool. A soft plastic case guard, as
well as a sturdy hand strap, should give the Mastertech the
ability to survive in the often hostile shop environment.
A multi-function cartridge allows the Mastertech to function as
a scope and DMM for diagnostic work on any vehicle, regardless
of manufacturer. When working on late model vehicles, an OBD
II cartridge is available for the Mastertech’s second port. With
the proper cartridge, the Mastertech can display Enhanced OBD
II information for certain GM, Ford, and Chrysler domestics,
plus Toyota, Honda, Isuzu, and Suzuki vehicles. Enhanced OBD
II parameters go beyond strictly emissions-related information.
The Mastertech’s LCD display measures 2.75 inches square,
with a resolution of 160 x 160 pixels. With the next software
update, the screen will update four times per second in scope
mode at 1 mS/Division. There is a backlight and contrast
adjustment. To look at a captured waveform with greater detail,
the Zoom function allows you to zoom in on a part of the waveform to see all of the information that was captured by the
scope in its oversampling “glitch capture” mode.
12
February 1998