Launch X431 Scopebox User Manual
LAUNCH X431 PAD Scopebox User’s Manual
Precaution on Operation
z The appliance is a sophisticated electronic device, never have it clashed
when in use.
z Main unit screen may flash at the moment of engine ignition, which is
normal.
z You may unplug the main unit if the program can not be actuated or
confused screen occurs. Plug again to continue the operation.
z Make sure the appliance is properly connected to the DLC to avoid
communication interruptions.
z During operation, keep the screen upward and leveled.
z Be careful when plugging and unplugging the main cable and diagnostic
connector. Tighten the screw before operation to avoid unexpected
disconnecting and/or damage to the port.
z Handle with care. Avoid collision. Unplug the power after operation.
z After the operation, the stylus shall be inserted into the slot on the main
unit, and put away the cable and connector, etc accessories to the box to
avoid the lost.
z Unplug the power cable by holding the connector, not the cable itself.
LAUNCH X431 PAD Scopebox User’s Manual
Table of Contents
1 FOREWORD......................................................................................1
1.1
INTRODUCTIONS ...........................................................................1
1.2
PRODUCT FEATURES.....................................................................1
1.3
PRODUCT FUNCTION.....................................................................2
1.4
TECHNICAL PARAMETERS ..............................................................2
2 STRUCTURE AND ACCESSORIES ................................................. 3
2.1
SCOPEBOX STRUCTURE................................................................3
2.2
SCOPEBOX ACCESSORIES............................................................. 4
3 AUTOMOTIVE OSCILLOSCOPE......................................................6
3.1
CONNECTION................................................................................ 6
3.2
INITIAL INTERFACE INTRODUCTION.................................................6
3.3
OPERATIONS.................................................................................7
3.3.1 Channel selection and attributes
setting
..............................7
3.3.2 Trigger setting.......................................................................9
3.3.3 A
uto cal
i
bration...................................................................11
3.3.4 Display settings ................................................................. 12
3.3.5 Channel and cursor meas
ur
ement.................................... 12
3.3.6 File management...............................................................
13
3.3.7 View the softw
a
re version ................................................. 15
3.3.8 Exit the application............................................................
15
4 AUT OMOTIVE IGNITION WAVEFORM .......................................... 16
4.1
SECONDARY-DISTRIBUTOR IGNITION ANALYSIS............................. 16
4.2
SECONDARY-SIMULTANEOUS IGNITION ANALYSIS.......................... 19
4.3
SECONDARY-DIRECT IGNITION ANALYSIS...................................... 20
4.4
WA VEFORM ANAL YSIS MODE........................................................ 22
LAUNCH X431 PAD Scopebox User’s Manual
1
1 Foreword
1.1 Introductions
X-431 PAD is a new generation of sophisticated and integrated automotive
diagnostic product with colorful screen and powerful functions developed by
LAUNCH, and Scopebox is an optional function box for X-431 PAD , including
automotive oscilloscope and automotive ignition waveform.
Automotive oscilloscope can make the auto repair technician quickly judged
the fault
s on automotive electronic equi
pment and wiring, and the oscilloscope
sweep speed is far greater than the signal frequency of such vehicles, usually
5-10 times of the measured signal. The automotive oscilloscope not only can
quickly capture the circuit signal, but also can slowly display the waveform to
observe and analyze. It can also record and store the tested signal waveform
which can be played back to observe for the fast signal, having great
convenience to failure analysis. Either high-speed signal (e.g.: injection nozzle,
intermittent fault signal) or the slow-speed signal (e.g. the throttle position
change and the oxygen sensor signal) can be observed through automotive
oscilloscope in an appropriate waveform.
The electronic signal can be compared and judged via measuring five
parameters index
es. The five parameters indexes are the amplitude (the
maximum voltage of signal), the frequency (the cy cle time of signal), the shape
(the appearance of signal), the pulse width (the duty cycle or the time range of
signal), and the array (the repetition characteristic of signal), which can be
tested, displayed, saved by the automotive oscilloscope. Via the waveform
analysis can further detect the circuit fault on sensors, actuators, circuits, and
electronic control units, etc.
1.2 Product features
z Rapidly capture the circuit signal.
z Display waveform slowly for observation and analysis.
z Record and store the tested signal waveform for playback and failure
analy
sis.
LAUNCH X431 PAD Scopebox User’s Manual
2
z Detect, display and store all the electrical signal of five parameters,
namely amplitude, frequenc
y, shape, pulse width, and array.
1.3 Product function
Provides specialized automotive oscilloscope function and supports ignition
waveform analysis.
1.4 Technical parameters
Scopebox: 4 channels, highest sampling frequency 200MHZ, max storage
depth 64MSa, 8-bit resolution.
LAUNCH X431 PAD Scopebox User’s Manual
2 Structure and Accessories
2.1 Scopebox structure
Fig 2-1 Scopebox Structure Diagram
Table 2-1 shows the ports and indicators for X-431 PAD Scopebox
No. Name Description
1 CH1 Channel 1
2 CH2 Channel 2
3 CH3 Channel 3
4 CH4 Channel 4
5 External trigger External trigger signal
6 Fixed signal
generator
Generate a square signal with fixed 1K frequency
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LAUNCH X431 PAD Scopebox User’s Manual
7 Power indicator Oscilloscope power indicator, which will be steady
red after the oscilloscope is powered on
8 Operating
indicator
The indicator will be steady green after the
oscilloscope operated.
9 Communication
indicator
After the data communication, the indicator will
blink (Green).
10 Power interface Connect to power supply via the power adapter.
11 B-shaped USB
interface
Connect main unit via USB connect line as
separated individual USB devices
2.2 Scopebox accessories
Scopebox includes the secondary pickup cable for 4-channel oscilloscope,
crocodile clips for 4-channel oscilloscope, etc. See Table 2-2.
As the product configuration can be different, the accessories inc
luded with the
product may differ from the accessories listed on this manual. Please see the
packing list attached to the product for the detailed accessor ies.
Table 2-2 Accessory checklist
No. Name Picture
1 Secondary ignition pickup for
4-channel oscilloscope
2 Crocodile clips for 4-channel
Oscilloscope
3 Direct ignition extension cord
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LAUNCH X431 PAD Scopebox User’s Manual
4 6-way universal guide line for
4-channel oscilloscope
5 BNC to 4mm connector test
cable
6 Pin connector for 4-channel
oscilloscope
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LAUNCH X431 PAD Scopebox User’s Manual
6
3 Automotive Oscilloscope
3.1 Connection
X-431 PAD Scopebox should work with the X431 PAD main unit.
1. Firstly, power on the main unit (Connect one end of the power adaptor into
the power interface of main unit, and
the other end to the DC 12V power
supply. Alternatively it can be also powered by cigarette lighter cable and
double clip power cord).
2. Then plug one end of ground cable of oscilloscope into ex
ternal trigger
channel (GND), the other end should be grounded.
3. Connect one end of probe cable of oscilloscope
to the CH1, CH2, CH3, or
CH4 on oscilloscope module, and then connect the other end to related
signal terminal.
Warning: please use the specific capacitance probe when diagnosing the
ignit
ion high voltage line. Never connect the oscilloscope to the ignition
secondary circuit directly.
3.2 Initial interface introduction
Fig. 3-1 displays the initial interface of oscilloscope.
LAUNCH X431 PAD Scopebox User’s Manual
Fig.3-1
Button descriptions:
[Autoset]: It indicates a
u
to trigger setting. Based on the characteristics of
measured signal, the oscilloscope will automatically set the horizontal bas eline,
vertical sensitivity and trigger condition so that the waveform can be display ed.
[File]: provide
s
waveform record and waveform replay.
[View]:
Calibration and display settings are available.
[Measure]
: includes signa
l source measurement, cursor measurement and
clear measurement.
[Settings]: display
s or hides the parameter settings area including horizontal
settings, vertical settings and trigger settings.
[Start/stop]: start
s/stops collecting oscilloscope waveforms.
3.3 Operations
3.3.1 Channel selection and attributes setting
<1> Channel selection
There are two ways available for channel selection: (See Fig. 3-2)
A. Select from the channel column shown at the bottom of the waveform
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LAUNCH X431 PAD Scopebox User’s Manual
display area;
B. Select from Vertical settings.
Note: For better comparison and identification, each channel and waveform
are marked in dif
f
erent colors.
Fig.3-2
<2> Channel attributes setting
Channel attributes can be set via horizonta
l settings and vertical settings.
Horizontal Settings
User can make some settings directly by clicking << or >> next to options.
Alternatively
, Click
located in the upper right corner of the horizontal
settings to make more settings. See Fig. 3-3.
Fig. 3-3
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LAUNCH X431 PAD Scopebox User’s Manual
Options descriptions:
Time/DIV: click << or >> to adjust;
Y-T Format: click << or >> to adjust. It includes 3 options: Normal, Scan and
Scroll (from ri
ght to left).
V ertical Setting s
User can make some settings directly by clicking << or >> next to options.
Alternatively
, Click
located in the upper right corner of the vertical settings
to make more settings. See Fig. 3-4.
Fig. 3-4
Options descriptions:
A. Channel selection;
B. Channel switch selection;
C. Channel voltage adjustment;
D. Channel coupling modes sele
ction: DC,
AC or Ground;
E. Channel probe selection;
F. Bandwidth limit switch;
G. Channel reverse phase switch.
3.3.2 Trigger setting
Trigger indicates that when certain waveform meets the conditions that are
predefined according to the requirements, the oscilloscope captures the
waveform and its adjacent section, and then presents it on the screen.
<1> T r igger mo de
It is classified into 3 categories: Pulse Width and Edge.
[Edge]: It is the most common and ef
fective trigger mode, which is widely used
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LAUNCH X431 PAD Scopebox User’s Manual
in most applications. Edge trigger only detects the edges, polarities, and
voltage of signal. When the voltage of measured signal varies as identical as
the preset one (rising edge or falling edge), and the value becomes same as
trigger voltage, the oscilloscope will be triggered and capture the waveform.
[Pulse Width]: T
rigger happens when it reaches to the pulse width.
Fig. 3-5 and Fig. 3-6 show edge trigger, pulse widt
h trigger setting interfaces.
Fig. 3-5
Fig. 3-6
<2> Trigger Sweep
Auto, Normal and Single are included.
Auto: It indicates that no matter w
hether it meets the trigger conditions, it will
refresh the waveform in real time. In this case, the waveform displ ayed on the
screen seems swaying;
Normal: Only
it meet
s the trigger conditions can trigger be activated.
Otherwise the waveform will keep still.
Single: In this mode, it only
captures the waveform that generates for the first
time the trigger conditions are met, and then stops after finishing capture.
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LAUNCH X431 PAD Scopebox User’s Manual
<3> Trigger source
Trigger source means w hich channel signa l w ill be measured as trigger object.
Before making settings to trigger mode and v
oltage of certain channel, you
have to choose the target channel.
3.3.3 Auto calibration
This option enables you to obtain a precise measurement of measured signal.
Auto calibration mainly includes: calibration of analog channel, trigger voltage
calibration of trigger circuit and nonlinear calibration of horizontal baseline
movement.
Click “View” and then click [Calibration], a dialog box simil
ar to Fig. 3-8 will
appear.
Fig. 3-8
Check the box before the channel to select it. T
o select all, click [Check All]. To
deselect it, just click [Reverse]. After choosing the desired channel(s), click
[Start] to start calibration and [Calibration] button will be temporarily invalid
during calibrating. Click [Stop] to stop calibrating. Once it becomes active, it
indicates calibration has completed.
Notes: In process of calibration, make sure CH1/CH2/CH3/CH4 has no signal
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LAUNCH X431 PAD Scopebox User’s Manual
input. Moreover, calibration may take several minutes and please be patient to
wait.
3.3.4 Display settings
Click “View” and then [Display settings] to enter the setting screen. See Fig.
3-9.
Fig. 3-9
Click “Vectors” or “Dots” to define display
mode. Check/uncheck the box
before Grid to open/close grid display.
3.3.5 Channel and cursor measurement
<1> Channel measurement
Click “Measure” and then [Source], a screen similar to Fig. 3-10 will appear.
Fig. 3-10
<2> Cursor measurement
Click “Measure” and then [Cursor Measure], a screen similar to Fig. 3-11 will
appear.
Not
e: if no desired channel is selected, the system will take the current source
as the default channel.
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LAUNCH X431 PAD Scopebox User’s Manual
Fig. 3-11 Fig. 3-12
Horizontal Measure is for voltage (see Fig. 3-11) and vertical measure is for
timebase (see Fi
g. 3-12).
Options descriptions:
[A Line / B Line move up / do wn]: fine adjustment for volt
age. A line is a solid
line and B line is a dotted line;
[A Line / B Line move left / right]: fine adju
stment for timebase. A line is a
solid line and B line is a dotted line.
<3> Clear Measurement
Click “Measure” and then [Clear Measure], the s
ystem will clear the
measurement result.
3.3.6 File management
<1> Record waveform
This function is used to record waveforms that are collected by oscilloscope at
a period, and save it as dat
a file which can be played back in future.
It can be performed only when the oscilloscope is collecting data in Normal
mode.
Click [File], then select [Record] from the pop-up menu to start recording.
See
Fig. 3-13.
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LAUNCH X431 PAD Scopebox User’s Manual
Fig.3-13
Click [Record] to start recording, and the Record button becomes S
top button.
Click [Stop] to stop recording. While recording, the recorded pages will be
shown on the screen.
<2> Import waveform for playback
The Import function enables you to import the stored waveform file for
playback and review
. During replaying, the oscilloscope stops collecting data
automatically.
Click [File], then select [Waveform replay] from the pop-up menu to enter
a
screen similar to Fig. 3-14.
Fig.3-14
Select the playback file first, and then click [OK] button to open the
waveform
file, then use channel attributes setting to adjust the waveform display.
To delete the waveform file, please enter “My Data” and choose the
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LAUNCH X431 PAD Scopebox User’s Manual
corresponding folder to perform delete operation.
<3> Print waveform
This option allows you to print out the latest collected dat
a while the
oscilloscope stops collecting dat a. While printin g, the oscilloscope should be in
stop mode.
Click
on the shortcut bar to start printing.
3.3.7 View the software version
Click to view the version information of the oscilloscope.
3.3.8 Exit the application
Click to exit the current application.
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16
4 Automotive Ignition waveform
The ignition system is the system which has greatest impact on the
performances of gasoline engine, as the statistical data shows that nearly half
of the failures are caused by poor work of electrical system. And the
performance tests of engine often start from the ignition system. Nowadays
ignition system includes distributor and distributorless. Distributorless includes
independent ignition and simultaneous ig nition.
1. Distributor ignition system i.e. contact break
er with contact-controlled
ignition system (commonly known as the platinum) and contact breaker
with noncontact-controlled ignition system combined with magnet, hall
components or infrared.
2. Independent ignition system: crankshaft sensor send out the ignition
timing si
gnal and cylinder identification signal so that the ignition system
can send out ignition signal to specified cylinder in specified time, each
cylinder has its independent ignition coil.
3. Simultaneous ignition system: two cylinders share one ignition coil, when
two c
ylinder pistons reach top dead center at the same time (one is
compression, another is the exhaust), two spark plugs will be ignited at
the same time, at this time, the ignition for the former cylinder is in
high-pressure low temperature gas mixture, the ignition is valid, while for
the latter one is in low-pressure high temperature exhaust gas, the
ignition is invalid.
X-431 PAD can test and analyze the secondary signal for various engine
ignit
ion systems.
4.1 Secondary-distributor ignition analysis
Connections: Plug the BNC end of secondary ignition pickup into
CH1/CH2/CH3/CH4 channel of Scopebox, then connect the high-voltage clip
to high-voltage line, and crocodile clips to groun d.
Tips: Common ignition sequence (the specific sequence is subject to the
actual engine ig
nition sequence)
LAUNCH X431 PAD Scopebox User’s Manual
17
Four-stroke in-line four-cylinder: 1—2—4—3, or 1—3—4—2
Four-stroke in-line six-cylinder: 1—5—3—6—2—4, or 1—4—2—6—3—5
Four-stroke in-line eight-cylinder: 1—8—4—3—6—5—7—2
Five-cylinder: 1-2-4-5-3
V 6 engine: generally speaking, based on the person sitting on the driver cab,
if the right side
cylinder numbers on the right side, from the front to the back
are as follows: 1, 3, 5; and the cylinder numbers on the left side, from the front
to the back are as follows: 2, 4, 6; then the ignition sequence is: 1－4－5－2－
3－6. If the cylinder numbers on the right side, from the front to the back are as
follows: 2, 4, 6; and cylinder numbers on the left side, from the front to the back
are as follows:1, 3, 5; then the ignition sequence is: 1－6－5－4－3－2.
The Figure 4-1 below shows the normal ignition w aveform of distributor ignition
s
y
stem, the upper one is the secondary waveform, and the lower one is the
primary waveform.
The secondary waveform
A section is cont act open per iod; B section is make cont act perio d, which is the
magnetizing field of ignition coil.
LAUNCH X431 PAD Scopebox User’s Manual
Fig. 4-1
1) Contact break point: the primary circuit of igniti
on coil cut off, the
secondary voltage was sensed and increased sharply
2) Ignition voltage: secondary coil volta
ge overcome the damper of high
voltage line, the contact breaker gap and the spark plug gap to release
magnetizing energy, 1-2 section is the breakdown voltage
3) Spark voltage: For the capacitor discharge voltage
4) Ignition voltage pulse: For the charge and discharge sections
5)
Spark line: The inductance discharge process, i.e. the mutual induct
ance
voltage of ignition coil maint ains the conduction of secondary circuit
6) Contact point close the current flow into
primary coil, the primary coil
oscillates due to the mutual inductance.
Primary ignition waveform
Section
a shows the voltage oscillation on the primary circuit due to the
magnetic induct
ion of spark in the duration;
Section b shows the damped oscillation genera
ted by remaining magnetic field
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LAUNCH X431 PAD Scopebox User’s Manual
energy after the spark;
Section c shows the make cont
act magneting period of primary coil.
Seen from the waveform, the amplitudes of breaker contact closed angle,
break angle and
breakdown voltage and spark voltage are very clear, besides,
the spark delay period and two oscillations can also be tested. For the ignition
system without faults, compared with the whole cycle, the cont act closed ang le
just 45%-50% (four-cylinder), 63%-70% (six-cylinder), or 64%-71%
(eight-cyliner); the breakdown voltage is over 15kv; the spark voltage is about
9kV, the spark period is greater than 0.8ms. If these values or waveform are
abnormal, it means there is fault or the system needs to be adjusted.
4.2 Secondary-simultaneous ignition analysis
Connections: Plug the BNC end of secondary ignition pickup into
CH1/CH2/CH3/CH4 channel of Scopebox, then connect the high-voltage clip
to high-voltage line, and crocodile clips to groun d.
Connection as shown in figure 4-2:
Fig. 4-2
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LAUNCH X431 PAD Scopebox User’s Manual
Fig. 4-3 below shows the valid and invalid ignition waveforms. Under the
working status of valid ignition, the breakdown voltage and spark voltage are
higher because the cylinder is filled with fresh combustible mixture gas, which
has a lower ionization level and vice versa.
Fig. 4-3
4.3 Secondary-direct ignition analysis
Connection：
1) When the high-voltage wire is exposed, plug the BNC end of secondary
ignit
ion pickup into CH1/CH2/CH3/CH4 channel of Scopebox, then
connect the high-voltage clip to high-voltage line, and crocodile clips to
ground.
2) If no high-voltage wire exposes, dismantle ignition coil of tested cylinder
and use direct
ignition extension cord. Connect one end to ignition coil
which should be grounded via direct ignition grounding wire, and insert the
other end into cylinder to joint with spark plug. Then plug the BNC end of
secondary ignition pickup into CH1/CH2/CH3/CH4 channel of Scopebox,
then connect the high-voltage clip to high-voltage line, and crocodile clips
to ground.
Connections are shown in Fig. 4-4:
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LAUNCH X431 PAD Scopebox User’s Manual
Fig. 4-4
Fig. 4-5 shows the normal secondary (the upper one) and
(the lower one)
primary ignition waveform of direct ignition system. Beause the on/off of
primary circuit is not opening/closing of mechanical contact, but the conduction
of transistor. The primary voltage has no obvious oscillations within the
duration, but the voltage increases during the magnetization process due to
current limiting, and this change can cause corresponding fluctuations of
secondary voltage line as a result of induction of ignition coil.
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LAUNCH X431 PAD Scopebox User’s Manual
Fig. 4-5
4.4 Waveform analysis mode
The ignition secondary single-cylinder waveform test is mainly used to:
a. Analyze the ignition dwell angle of single cy
linder.(ignition coil charging
time)
b. Analyze the capability of ignition coil and secondary high tension circuit
(from ignition line
to ignition voltage line).
c. Find the improper mixture A/F ratio of single cylinder (from co
mbustion
line).
d. Analyze the capability of capacitance (platinum or ignition sy
stem).
e. Find the spark plug that causes misfire of the c
ylinder (from combustion
line).
This test can provide very meaningfu
l information about the combustion quality
for each cylinder. If necessary, this test can also be performed during driving.
Since the secondary ignition waveform is significantly affected by different
engines, fuel systems and ignition conditions, it is useful for detecting the faults
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LAUNCH X431 PAD Scopebox User’s Manual
23
of engine mechanical parts, fuel system components, and
ignition system
components. Different parts of the waveform can specify that some
components and systems on the specific cylinder have faults. Refer to the
instructions for various parts of waveform for the related component working
status of specific waveform section.
Test methods and conditions:
Start the engine or drive the vehicle accroding
to the driving performance fault
or poor ignition, etc. Confirm the consistence of judgement standard (the
amplitude, frequency, shape and pulse width, etc., for each cylinder), check
the fault of the waveform for corresponding components.
Waveform results: observe the ignition coil at the beginning of charging, the
relative cons
istent falling edge represents the dw ell angle and ignitio n timing of
each cylinder are precise.
Ignition line:
Observe the height consistence of flashover voltage. Too high flashover
voltage (even out of the oscillosco
pe screen) represents a high resistance
existed in the ignition secondary circuit (for example, open circuit, or damaged
spark plug or high voltage line, or too large time gap on spark plug), while the
too short sparking voltage represents the resistance of ignition secondary
circuit is lower than normal value (due to pollut ant and broken s park plug or the
high voltage line of spark plug has electric al leakage, etc.).
Spark or combustion voltage:
Observe the consistence of spark or combustion voltage, as it represents the
consistence of sp
ark plug and the air-fuel ratio of each cylinder. In case that
the mixing ratio is too lean, the combustion voltage will be lower than normal
value.
Combustion line:
Observe the spark or the combustion line which shall be clean with few clutter,
as lots
of clutter indicates the cylinder has poor ignition due to ignite too early,
damaged nozzle, pollutant spark plug, or other reasons. The duration of
combustion line indicates the mixing ratio of the cylinder is abnormal lean or
LAUNCH X431 PAD Scopebox User’s Manual
rich. Too long combustion line (usually greater than 2ms) represents the mixing
ratio is rich, whereas too short of combustion line (usually less than 0.75ms)
represents the mixing ratio is lean.
Ignition coil oscillation:
Observe at least two oscillation w aveforms af ter the combustion line, which w ill
be better if more than three oscillation w
aveforms, as it represents the ignition
coil and capacitor (on Platinum or ignition system) are normal.
Primary voltage analysis
According to the faulty primary voltage waveform collected by the ignition
analysis, the rel
ated components and mechanical equipment status of ignition
system electrical circuit can be analyzed, which provides a reliable basis for
the adjustment and maintenance of power circuit to avoid the blind demolition.
The waveform shown on Fig. 4-6, appears a lot of clutter on the contact break
point, which is obviou
sly caused by the serious erosion on contact break point.
It can be verified via burnishing the contact or changing the circuit breaker.
Fig. 4-6
For the primary voltage waveform shown on Fig
. 4-7, the damped attenuation
cycles obviously reduced on the spark period, the amplitude became lower,
which is evidently caused by capacitor leakage.
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LAUNCH X431 PAD Scopebox User’s Manual
Fig. 4-7
The waveform on Fig. 4-8, shows the accide
ntal pumping during contact
closing period. The irregular beating is caused by insufficient spring force.
Fig. 4-8
The curve on Fig. 4-9 shows the contact angle is too small during the
magnetizing per
iod, which is caused by too large contact gap.
Fig. 4-9
A lot of clutter will be display ed on the horizont
al section of primary waveform if
contact has poor grounding, as shown below figure 4-10.
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LAUNCH X431 PAD Scopebox User’s Manual
Fig.4-10
Fig. 4-11 shows the fault of low-voltage waveform in electronic ignitio
n system.
The voltage does not rise during magnetiz ing, w hich ind icates that the effect of
limitation of the circuit failed and no components on distributorless ignition
system can be adjusted. When this waveform is abnormal, you can only
replace the ignition coils, igniter, ignition signal generator and cam position
sensor, etc., one by one, to find out the faulty component or module.
Fig. 4-11
The secondary waveform is also affected by the spark plug, the combustion
process, mixt
ure gas composition, the engine thermal state of the ignition coil,
etc., which is more complicated. The following lists a large number of
measured secondary faulty waveform for reference. Since various factors lead
to the failures, Fig. 4-12 just shows the major possible factors for the failures.
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LAUNCH X431 PAD Scopebox User’s Manual
Fig 4-12
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