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Version Info
Version
Date
Remarks
V1.0
2024.01
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Preface
Preface
Dear customers,
Congratulations! Thank you for buying Micsig instrument. Please read this manual carefully before use and
particularly pay attention to the “Safety Precautions”.
If you have read this manual, please keep it properly for future reference.
The information contained herein are furnished in an “as-is” state, and may be subject to change in future versions
without notice.
The standard applicable for this product: GB/T15289-2013.
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Table of Contents
i
Table of Contents
TABLE OF CONTENTS ......................................................................................................................................................... I
CHAPTER 1. SAFETY PRECAUTIONS ................................................................................................................................... 1
1.1 SAFETY PRECAUTIONS .................................................................................................................................................... 1
1.2 SAFETY TERMS AND SYMBOLS ........................................................................................................................................ 5
CHAPTER 2. QUICK START GUIDE OF OSCILLOSCOPE ......................................................................................................... 8
2.1 INSPECT PACKAGE CONTENTS ........................................................................................................................................ 8
2.2 FRONT PANEL ................................................................................................................................................................ 9
2.3 REAR PANEL ................................................................................................................................................................ 10
2.4 POWER ON/OFF THE OSCILLOSCOPE............................................................................................................................... 11
2.5 CONNECT THE OSCILLOSCOPE ....................................................................................................................................... 11
2.6 UNDERSTAND THE OSCILLOSCOPE DISPLAY INTERFACE ................................................................................................. 17
2.7 INTRODUCTION BASIC OPERATIONS OF TOUCH SCREEN ................................................................................................. 23
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2.8 USE AUTO .................................................................................................................................................................... 25
2.9 LOAD FACTORY SETTINGS ............................................................................................................................................ 27
2.10 USE AUTO-CALIBRATION ............................................................................................................................................ 27
2.11 PASSIVE PROBE COMPENSATION ................................................................................................................................. 28
2.12 MODIFY THE LANGUAGE ............................................................................................................................................ 33
CHAPTER 3 AUTOMOTIVE TEST ....................................................................................................................................... 34
3.1 CHARGING/START CIRCUIT .................................................................................................................................................. 34
3.1.1
12V Charging .................................................................................................................................................... 36
3.1.2
24V Charging .................................................................................................................................................... 38
3.1.3
Alternator AC Ripple ......................................................................................................................................... 39
3.1.4
Ford Focus Smart Generator ............................................................................................................................... 40
3.1.5
12V Start ............................................................................................................................................................ 42
3.1.6
24V Start .......................................................................................................................................................... 45
3.1.7
Cranking Current .............................................................................................................................................. 46
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3.2 SENSOR TESTS ................................................................................................................................................................ 48
3.2.1
ABS ..................................................................................................................................................................... 49
3.2.2
Accelerator pedal ............................................................................................................................................... 51
3.2.3
Air Flow Meter .................................................................................................................................................... 53
3.2.4
Camshaft ............................................................................................................................................................ 56
3.2.5
Coolant Temperature .......................................................................................................................................... 59
3.2.6
Crankshaft .......................................................................................................................................................... 61
3.2.7 Distributor ............................................................................................................................................................. 63
3.2.8
Fuel pressure ...................................................................................................................................................... 65
3.2.9
Knock .................................................................................................................................................................. 67
3.2.10
Lambda ............................................................................................................................................................ 69
3.2.11
MAP ................................................................................................................................................................. 72
3.2.12
Road Speed ....................................................................................................................................................... 75
3.2.13
Throttle Position ............................................................................................................................................... 77
3.3 ACTUATORS .................................................................................................................................................................... 79
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3.3.1
Carbon canister solenoid valve ........................................................................................................................... 79
3.3.2
Disel Glow Plugs ................................................................................................................................................. 81
3.3.3
EGR Solenoid Valve ............................................................................................................................................. 83
3.3.4
Fuel Pump .......................................................................................................................................................... 85
3.3.5
Idle speed control valve .................................................................................................................................... 87
3.3.6
Injector (gasoline engine) ................................................................................................................................. 89
3.3.7
Injector (Diesel) .................................................................................................................................................. 91
3.3.8
Pressure regulator ............................................................................................................................................ 93
3.3.9
Quantity (Flow) control valve ............................................................................................................................. 95
3.3.10
Throttle Servo Motor ........................................................................................................................................ 97
3.3.11
Variable speed cooling fan ................................................................................................................................ 99
3.3.12
Variable valve timing ...................................................................................................................................... 101
3.4 IGNITION TESTS ............................................................................................................................................................. 103
3.4.1
Primary............................................................................................................................................................. 103
3.4.2
Secondary ......................................................................................................................................................... 107
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3.4.3
Primary + Secondary......................................................................................................................................... 109
3.5 NETWORKS .................................................................................................................................................................. 112
3.5.1
CAN High & CAN Low ....................................................................................................................................... 112
3.5.2
LIN Bus ............................................................................................................................................................. 115
3.5.3
FlexRay Bus ...................................................................................................................................................... 117
3.5.4
K line ................................................................................................................................................................ 120
3.6 COMBINATION TESTS ...................................................................................................................................................... 122
3.6.1
Crankshaft + Camshaft ..................................................................................................................................... 122
3.6.2
Crankshaft + Primary ignition ........................................................................................................................... 124
3.6.3
Primary ignition + Injector voltage ................................................................................................................... 126
3.6.4
Crankshaft + Camshaft + Injector + Secondary Ignition .................................................................................... 128
CHAPTER 4 HORIZONTAL SYSTEM .................................................................................................................................. 130
4.1 MOVE THE WAVEFORM HORIZONTALLY ...................................................................................................................... 132
4.2 ADJUST THE HORIZONTAL TIME BASE (TIME/DIV) ....................................................................................................... 133
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4.3 PAN AND ZOOM SINGLE OR STOPPED ACQUISITIONS .................................................................................................... 136
4.4 ZOOM MODE ........................................................................................................................................................... 137
CHAPTER 5 VERTICAL SYSTEM ....................................................................................................................................... 141
5.1 OPEN/CLOSE WAVEFORM (CHANNEL, MATH, REFERENCE WAVEFORMS) ..................................................................... 143
5.2 ADJUST VERTICAL SENSITIVITY .................................................................................................................................. 148
5.3 ADJUST VERTICAL POSITION ....................................................................................................................................... 149
5.4 OPEN CHANNEL MENU ............................................................................................................................................... 150
5.4.1 Set Channel Coupling ........................................................................................................................................... 151
5.4.2 Set Bandwidth Limit ............................................................................................................................................ 153
5.4.3 Waveform Inversion ............................................................................................................................................ 154
5.4.4 Set Probe Type ..................................................................................................................................................... 155
5.4.5 Set Probe Attenuation Coefficient ........................................................................................................................ 156
5.4.6 Vertical expansion datum .................................................................................................................................... 158
5.4.7 Channel label ....................................................................................................................................................... 158
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CHAPTER 6 TRIGGER SYSTEM ........................................................................................................................................ 160
6.1 TRIGGER AND TRIGGER ADJUSTMENT ......................................................................................................................... 161
6.2 EDGE TRIGGER ........................................................................................................................................................... 173
6.3 PULSE WIDTH TRIGGER .............................................................................................................................................. 177
6.4 SERIAL BUS TRIGGER ................................................................................................................................................. 184
CHAPTER 7 ANALYSIS SYSTEM ....................................................................................................................................... 185
7.1 AUTOMATIC MEASUREMENT ....................................................................................................................................... 186
7.2CURSOR ...................................................................................................................................................................... 197
7.3 PHASE RULERS ........................................................................................................................................................... 203
CHAPTER 8 STORAGE .................................................................................................................................................... 204
8.1 SCREEN CAPTURE FUNCTION ...................................................................................................................................... 205
8.2 WAVEFORM STORAGE ................................................................................................................................................ 205
8.3 OSCILLOSCOPE SETTING SAVE ..................................................................................................................................... 211
CHAPTER 9 MATH AND REFERENCE ............................................................................................................................... 213
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9.1 DUAL WAVEFORM CALCULATION ............................................................................................................................... 214
9.2 FFT MEASUREMENT .................................................................................................................................................. 219
9.3 REFERENCE WAVEFORM CALL .................................................................................................................................... 227
CHAPTER 10 DISPLAY SETTINGS ..................................................................................................................................... 232
10.1 COMMON SETTINGS .................................................................................................................................................. 233
10.2 GRATICULE SETTING ................................................................................................................................................ 234
CHAPTER 11 SAMPLING SYSTEM ................................................................................................................................... 235
11.1 SAMPLING OVERVIEW ............................................................................................................................................... 236
11.2 RUN/STOP KEY AND SINGLE SEQ KEY ...................................................................................................................... 242
11.3 RECORD LENGTH AND SAMPLING RATE ..................................................................................................................... 243
CHAPTER 12 SERIAL BUS TRIGGER AND DECODE ........................................................................................................... 247
12.1 LIN BUS TRIGGER AND DECODE ............................................................................................................................... 250
12.2 CAN BUS TRIGGER AND DECODE ............................................................................................................................. 257
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CHAPTER 13 REFERENCE ............................................................................................................................................... 264
13.1 MEASUREMENT CATEGORY ....................................................................................................................................... 265
13.2 POLLUTION DEGREE ................................................................................................................................................. 267
CHAPTER 14 TROUBLESHOOTING .................................................................................................................................. 268
CHAPTER 15 SERVICES AND SUPPORT ........................................................................................................................... 273
ANNEX .......................................................................................................................................................................... 275
ANNEX A:MAINTENANCE AND CARE OF OSCILLOSCOPE ................................................................................................... 275
ANNEX B: ACCESSORIES .................................................................................................................................................. 278
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Chapter 1. Safety Precautions
1
Chapter 1. Safety Precautions
1.1 Safety Precautions
The following safety precautions must be understood to avoid personal injury and prevent damage to this product or
any products connected to it. To avoid possible safety hazards, it is essential to follow these precautions while using
this product.
⚫ Only professionally trained personnel can operate the maintenance procedure.
⚫ Avoid fire and personal injury.
⚫ Use proper power cord. Use only the power cord specified for this product and certified for the country/region
of use.
⚫ Connect and disconnect probes properly. Connect the instrument probe correctly, and its ground terminal is
ground phase. Do not connect or disconnect probes or test leads while they are connected to a voltage source.
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Disconnect the probe input and the probe reference lead from the circuit under test before disconnecting the
probe from the measurement product.
⚫ Ground the product. To avoid electric shock, the instrument grounding conductor must be connected to
earth ground.
⚫ Observe all terminal ratings. To avoid fire or shock hazard, observe all rating and markings on the product.
Consult the product manual for further information of ratings before making connections to the product.
⚫ User correct probes. To avoid excessive electric shock, use only correct rated probes for any measurement.
⚫ Disconnect AC power. The adapter can be disconnected from AC power and the user must be able to access the
adapter at any time.
⚫ Do not operate without covers. Do not operate the product with covers or panels removed.
⚫ Do not operate with suspected failures. If you suspect that there is damage to this product, have it inspected
by service personnel designated by Micsig.
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Chapter 1. Safety Precautions
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⚫ Use adapter correctly. Supply power or charge the equipment by power adapter designated by Micsig, and
charge the battery according to the recommended charging cycle.
⚫ Avoid exposed circuitry. Do not touch exposed connections and components when power is present.
⚫ Provide proper ventilation.
⚫ Do not operate in wet/damp conditions.
⚫ Do not operate in a flammable and explosive atmosphere.
⚫ Keep product surfaces clean and dry.
⚫ The disturbance test of all models complies with Class A standards, based on EN61326:1997+A1+A2+A3,
but do not meet Class B standards.
Measurement Category
The VATO series oscilloscope is intended to be used for measurements in Measurement Category I.
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Measurement Category Definition
Measurement category I is for measurements performed on circuits not directly connected to the MAINS. Examples
are measurements on circuits not derived from MAINS, and specially protected (internal) MAINS derived circuits.
In the latter case, transient stresses are variable; for that reason, the user must understand the transient withstand
capability of the equipment.
Warning
IEC Measurement Category. Under IEC Category I mounting conditions, the input terminal can be connected to the
circuit terminal with a maximum line voltage of 300Vrms. To avoid the risk of electric shock, the input terminal
should not be connected to the circuit with a line voltage greater than 300Vrms. Instantaneous overvoltage is
present in circuits that are isolated from the mains supply. The VATO series digital oscilloscope is designed to
safely withstand sporadic transient overvoltage up to 1000Vpk. Do not use this equipment for any measurements in
circuits where the instantaneous overvoltage exceeds this value.
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Chapter 1. Safety Precautions
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1.2 Safety Terms and Symbols
Terms in the manual
These terms may appear in this manual:
Warning. Warning statements indicate conditions or practices that could result in injury or loss of life.
Caution. Caution statements indicate conditions or practices that could result in damage to this product or
other property.
Terms on the product
These terms may appear on the product:
Danger indicates an injury hazard immediately accessible as you read the marking.
Warning indicates an injury hazard not immediately accessible as you read the marking.
Caution indicates a hazard to this product or other properties.
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Symbols on the product
The following symbols may appear on the product:
Hazardous Voltage Caution Refer to Manual Protective Ground Terminal
Chassis Ground Measurement Ground Terminal
Please read the following safety precautions to avoid personal injury and prevent damage to this product or
any products connected to it. To avoid possible hazards, this product can only be used within the specified
scope.
Warning
If the instrument input port is connected to a circuit with the peak voltage higher than 42V or the power exceeding
4800VA, to avoid electric shock or fire:
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Chapter 1. Safety Precautions
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⚫ User only insulated voltage probes supplied with the instrument, or the equivalent product indicated in the
schedule.
⚫ Before use, inspect voltage probes, test leads, and accessories for mechanical damage and replace when
damaged.
⚫ Remove voltage probes and accessories not in use.
⚫ Plug the battery charger into the AC outlet before connecting it to the instrument.
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Chapter 2. Quick Start Guide of Oscilloscope
This chapter contains checks and operations of the oscilloscope. You are recommended to read them carefully to
understand appearance, power on/off, settings and related calibration requirements of the VATO series oscilloscope.
2.1 Inspect Package Contents
When you open package after receipt, please check the instrument according to the following steps.
1) Inspect if there is any damage caused by transportation
If the package or foam is found to be severely damaged, please retain it until the instrument and accessories
pass the electrical and mechanical properties test.
2) Inspect the accessories
A detailed description is given in “Annex B” of this manual. You can refer it to check if the accessories are
complete. If the accessories are missing or damaged, please contact Micsig’s agent or local office.
3) Inspect the instrument
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Chapter 2. Quick Start Guide of Oscilloscope
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If any damage to oscilloscope is found by the appearance inspection or it fails to pass the performance test,
please contact Micsig’s agent or local office. If the instrument is damaged due to transportation, please retain
the package and contact the transportation company or Micsig’s agent, and Micsig will make arrangement.
2.2 Front Panel
Figure 2-1 Front Panel
The front panel includes the power on lock, power button, DC power port, Type-C interface, probe compensation
signal output, and cable clamp.
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2.3 Rear Panel
Figure 2-2 rear panel
The rear panel contains four analog channels Ch1 – Ch4
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Chapter 2. Quick Start Guide of Oscilloscope
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2.4 Power on/off the Oscilloscope
Power on/off the oscilloscope
Power on
⚫ Make sure the machine is powered by power and the POWER LOCK switch is on the left side. Press the power
button to turn on the instrument.
Power off
⚫ Long press the power button for forced power-off of the instrument.
Power-off lock
⚫ Turn the power-off lock switch to OFF(right), the oscilloscope cannot be turned on.
Caution: Forced power-off may result in loss of unsaved data, please use with caution.
2.5 Connect the oscilloscope
Connect to smartphone/tablet
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1. If the oscilloscope is powered by a power supply, please plug the adapter into the power socket first, and then
connect the DC end to the oscilloscope (if you are using battery power, you can ignore this step)
2. Use the provided Type-C data cable to connect the oscilloscope to a smartphone/tablet running Android 7 or
above.
3. Go to Micsig official website (https://www.micsig.com.cn/VATO/) to download the apk file, transfer it to the
device, open and install it
4. After completing the installation, open the software and grant permission to the floating window. The power
button of the oscilloscope will appear blue and flash, indicating that the connection is successful.
5. Connect the probe to the oscilloscope channel BNC connector, and then connect the retractable hook on the end
of the probe to the circuit point to be measured or the device under test. Be sure to connect the probe ground lead to
the ground point of the circuit.
Connect to PC
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Chapter 2. Quick Start Guide of Oscilloscope
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Since the emulator cannot recognize USB, VATO needs to install a virtual environment to connect to the computer.
You can use Vmware or VirtualBox virtual machine software to install Android 7 or above systems. Here we take
the Genymotion emulator and VirtualBox virtual machine software as an example:
1. Go to the Genymotion simulator website https://www.genymotion.com/download/ to download Genymotion with
VirtualBox
2. After the installation is completed, select and install the Android system suitable for your computer configuration
in the Genymotion emulator.
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Figure 2-3 Android virtual device installation
3. Connect the oscilloscope to the computer, open VirtualBox and enter settings, USB devices, click Add USB, find
Cypress, add and confirm
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Chapter 2. Quick Start Guide of Oscilloscope
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Figure 2-4 Setting USB device
4. Start the Android system installed on Genymotion, and drag the apk file downloaded from the Micsig official
website (https://www.micsig.com.cn/VATO/) into the Android desktop for installation. After completing the
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installation, open the software and grant floating window permissions. The power button of the oscilloscope turns
blue and flashes, indicating that the connection is successful.
Figure 2-5 Oscilloscope connected successfully
Maximum input voltage for analog input
Class I 300Vrms, 400Vpk.
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Chapter 2. Quick Start Guide of Oscilloscope
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2.6 Understand the Oscilloscope Display Interface
This section provides a brief introduction and description of the VATO series oscilloscope user’s interface. After
reading this section, you can be familiar with the oscilloscope display interface content within the shortest possible
time. The specific settings and adjustments will be detailed in subsequent chapters and sections. The following
items may appear on the screen at a given time but not all items are visible. The oscilloscope interface is shown in
Figure 2-6.
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Figure 2-6 Oscilloscope Interface Display
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Chapter 2. Quick Start Guide of Oscilloscope
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No.
Description
1
Click to open the top main menu, including measurement, save, display, trigger, user settings, about
2
The current trigger type and current trigger mode are displayed. A means Auto, N means Normal
3
Current trigger source, trigger level value
4
Trigger position
5
Current record length
6
Waveform display area center indication
7
Delay time, the time at which the center line of the waveform display area is relative to the trigger
point
8
Memory depth indicatrix
9
Current sample rate
10
The area in “[]” indicates the position of waveform displayed on the screen throughout the memory
depth
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No.
Description
11
Oscilloscope status includes running, stop, and waiting. Tap to switch to stop.
12
Automatically set, tap to enter the auto state, and the oscilloscope will automatically adjust the
waveform to a suitable display mode.
13
Single trigger, tap for single trigger
14
Click to open the channel menu of the current channel
15
Click to switch the current trigger source
16
The relevant information display area of each channel includes channel switch status, vertical
sensitivity, coupling mode, phase inversion, attenuation ratio, and bandwidth limit. Swipe left on
the corresponding channel to open the channel menu corresponding to the channel, click or to
adjust the vertical sensitivity of the channel
17
Trigger level indicator
18
Trigger level adjustment, drag up and down to adjust the trigger level
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Chapter 2. Quick Start Guide of Oscilloscope
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No.
Description
19
Phase scale to help measure timing of cyclic waveforms
20
The car repair soft bag has a variety of built-in car WeChat measurement items and can complete
oscilloscope settings with one click.
21
The current channel is forced to be selected. After clicking, the current channel switching menu
pops up to switch the current channel.
22
50% key: The channel zero point can be quickly returned to the center of the screen; the trigger
position can be quickly returned to the center of the screen; the trigger level can be quickly
Return to the center of the waveform; the cursor quickly returns to the center of the upper, lower,
left and right sides of the screen
23
Horizontal time base control icon. Tap the left/right button of the time base to adjust the horizontal
time base of the waveform. Tap the time base to open the time base matrix. Tap to select the
required time base.
24
Fast storage. Tap to quickly save the currently opened channel waveform as a reference waveform
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No.
Description
25
Fine adjustment buttons. Tap the fine-tuning button to fine-tune the waveform position, trigger
level position, trigger position, and cursor position.
26
Click to open the bottom shortcut menu, including ZOOM, full measurement, and cursor
27
Oscilloscope battery power display area
28
Horizontal time scale
29
Vertical direction voltage (current) scale
30
Channel Indicator: The displayed ground level of each analog channel signal, identified by the
channel indicator icon on the left side of the display
Table 2-1 Description of Oscilloscope Display Interface
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Chapter 2. Quick Start Guide of Oscilloscope
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2.7 Introduction Basic Operations of Touch Screen
The VATO series oscilloscope operates mainly by tap, swipe, single-finger drag.
Tap
Tap button on the touch screen to activate the corresponding menu and function. Tap any blank space on the screen
to exit the menu.
Swipe
Single-finger swipe: to open/close menus, including main menu, shortcut menu button and other channel menu
operations. For example, the main menu is opened as shown in Figure 2-7. The closing method is the opposite of
the opening method.
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Figure 2-7 Close the channel menu
Single-finger drag
For coarse adjustments of vertical position, trigger point, trigger level, cursor, etc. of the waveform. Refer to “4.1
Horizontal Move Waveform” and “5.3 Adjust Vertical Position” for details.
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Chapter 2. Quick Start Guide of Oscilloscope
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2.8 Use Auto
After correctly connecting the oscilloscope and inputting a valid signal, tap the Auto Setup button. Auto Setup can
quickly automatically configure the oscilloscope to display the best effect on the input signal. When the
oscilloscope enters the automatic state, the automatic button will turn green.
Each time you press "Auto", the oscilloscope can automatically adjust the vertical scale, horizontal scale and trigger
settings according to the amplitude and frequency of the signal, adjust the waveform to an appropriate size, and
display the input signal. After the adjustment is completed, exit Auto and the Auto button changes to blue.
Note: The application of Auto Set requires that the frequency of measured signal is no less than 20Hz, the
duty ratio is greater than 1% and the amplitude is at least 2mVpp. If these parameter ranges are exceeded,
Auto Set will fail.
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Figure 2-8 Open Auto Set
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Chapter 2. Quick Start Guide of Oscilloscope
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2.9 Load Factory Settings
Open the main menu, tap “User Settings” to enter the user setting page. Tap “Factory Settings” and the dialog box
for loading factory settings will pop-up. Press “OK” and load the factory settings. The dialog box for loading
factory settings is shown in Figure 2-9.
Figure 2-9 Load Factory Settings
2.10 Use Auto-calibration
Open the main menu, tap “Userset” to enter the user setting page. Tap “Self Adjust” to enter the auto-calibration
mode. When the auto-calibration function is active, the upper left corner of the screen displays “Calibrating” in red,
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and after calibrating is finished, the word in red disappears. When the temperature changes largely, the auto-
calibration function can make the oscilloscope maintain the highest accuracy of measurement.
⚫ Auto-calibration should be done without probe.
⚫ Auto-calibration process takes about two minutes.
⚫ If the temperature changes above 10℃, we recommended users perform the auto-calibration.
2.11 Passive Probe Compensation
Before connecting to any channels, users should make a probe compensation to ensure the probe match the input
channel. The probe without compensation will lead to larger measurement errors or mistakes. Probe compensation
can optimize the signal path and make measurement more accurate. If the temperature changes 10℃ or above, this
program must run to ensure the measurement accuracy.
Probe compensation may be conducted in the following steps:
1) First, connect the oscilloscope probe to CH1. If a hook head is used, make sure that it is in good connection
with the probe.
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Chapter 2. Quick Start Guide of Oscilloscope
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2) Connect the probe to the calibration output signal terminal and connect the probe ground to the ground
terminal. As shown in Figure 2-10.
Figure 2-10 Probe Connection
3) Open the channel (if the channel is closed).
4) Adjust the oscilloscope channel attenuation coefficient to match the probe attenuation ratio.
5) Tap button or manually adjust the waveform vertical sensitivity and horizontal time base. Observe the
shape of the waveform, see Figure 2-11.
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Figure 2-11 Probe Compensation
If the waveform on the screen is shown as “under-compensation” or “over-compensation”, please adjust the
trimmer capacitor until the waveform shown on the screen as “correct-compensation”. The probe adjustment is
shown in Figure 2-12.
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Chapter 2. Quick Start Guide of Oscilloscope
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Figure 2-12 Probe Adjustment
The safety ring on the probe provides a safe operating range. Fingers should not exceed the safety ring when using
the probe, so as to avoid electric shock.
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6) Connect the probe to all other oscilloscope channels (Ch2 of a 2-channel oscilloscope, or Ch 2, 3 and 4 of a 4-
channel oscilloscope).
7) Repeat this step for each channel.
Warning
⚫ Ensure the wire insulation is in good condition to avoid probe electric shock while measuring high voltage.
⚫ Keep your fingers behind the probe safety ring to prevent electric shock.
⚫ When the probe is connected a voltage source, do not touch metal parts of the probe-head to prevent electric
shock.
⚫ Before any measurement, please correctly connect the probe ground end.
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Chapter 2. Quick Start Guide of Oscilloscope
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2.12 Modify the Language
The language of the oscilloscope interface depends on the system language of the Android device. If you modify the
language of the Android system, the oscilloscope will automatically switch to the corresponding language.
Currently, it supports Simplified Chinese, Traditional Chinese, and English. For unsupported languages, it will
switch to English by default.
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Chapter 3 Automotive Test
This chapter contains most of the test applications of VATO automotive oscilloscopes in automotive circuits. The
purpose is to help users quickly troubleshoot and locate automotive electronics faults. It is recommended that you
read this chapter carefully to understand the general operation and use of automotive oscilloscopes.
3.1 Charging/Start Circuit
All electrical equipment of the car is powered by a power system composed of an on-board generator and a battery.
In this power system, the generator supplies power to the electrical equipment and charges the battery when the
generator is working normally. When the power generated by the generator is less than the power consumed by the
on-board electrical equipment, the battery participates in power supply to make up for its deficiency. When the
engine is working normally, it is necessary to ensure sufficient charging time for the battery to ensure that it does
not lose power. When the generator is working normally, whether to charge the battery can be indicated from the
charging indicator on the instrument panel. Due to the large speed range of the engine, the generator must be
equipped with a voltage regulator to ensure that its rated voltage is not affected by the speed and current. The power
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Chapter 3 Automotive Test
35
supply when the engine starts is completely provided by the battery, so the battery must ensure that there is enough
capacity to start the engine smoothly. The VATO series car-specific oscilloscope can test the charging circuit and the
starting circuit to test whether the charging/starting circuit of the car is working properly. The specific operations
are as follows:：
Click the icon in the lower right corner of the oscilloscope to display the screen shown in Figure 3-1：
Figure 3-1 Charging/Start Circuits
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3.1.1 12V Charging
12V charging is suitable for gasoline vehicles. Use a BNC to banana cable, one end is connected to channel 1 of the
oscilloscope, and the other end is connected to the positive and negative electrodes of the battery using two large
alligator clips (the red wire is connected to the red clip to the positive electrode, and the black wire is connected to
the black clip. negative electrode). If you need to measure current, please use a current clamp of 600A and above,
connect the BNC of the current clamp to channel 2, turn on the switch of the current clamp, and clamp the current
clamp to the output power line of the generator.
The alternator provides power to the vehicle. There is little difference between different manufacturers. The
charging voltage is generally between 13.5V and 15.0V. It is not good if it is too large or too small. The output
current of the generators of different models of different manufacturers is not the same, so it needs to be estimated
according to the vehicle.
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Chapter 3 Automotive Test
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Note: The generator adopts AC power generation. The voltage is converted to DC through multiple rectifier diodes.
The voltage can be measured by a multimeter. However, when the diodes are damaged, the multimeter displays the
correct readings, and the waveform can be judged by an oscilloscope.
The specific operation is shown in Figure 3-2:
Figure 3-2 12V Charging
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3.1.2 24V Charging
24V charging is suitable for diesel vehicles. The operation process is the same as that of 12V charging. The reference
voltage is 26.5V~30V. It can be tested with an oscilloscope. The specific operation is shown in Figure 3-3:
Figure 3-3 24V Charging
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3.1.3 Alternator AC Ripple
The VATO oscilloscope can test the charging ripple and assist the user to determine whether the charging process is
normal. Use a BNC to banana cable, one end is connected to the oscilloscope channel 1, and the other end is
clamped between the positive and negative electrodes of the battery (the red wire is connected to the red clip)
Connect the positive pole, and connect the black wire to the black clip to the negative pole). Start the vehicle and
start the test. At this time, the oscilloscope is coupled to AC, and what is displayed is not the true voltage value. It is
based on the DC waveform and the difference relative to the DC voltage.
As shown in Figure 3-4 below:
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Figure 3-4 Charging Ripple
3.1.4 Ford Focus Smart Generator
Use a BNC to banana cable, connect one end to channel 1 of the oscilloscope, connect the black plug to the black
alligator clip to ground (battery negative), and use a needle to connect the red connector to the engine ECM to
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generator output control line. Use BNC to banana cable, one end Connect to channel 2 of the oscilloscope, the other
black plug is connected to the black alligator clip to ground (the negative electrode of the battery), and the red
connector is connected to the feedback of the generator to the engine ECM with a stinger.
Use a current clamp of 600A and above, connect the BNC of the current clamp to channel 3, turn on the switch of
the current clamp, and clamp the current clamp to the output power line of the generator.
Start the vehicle and start the test. Among them, the control signal of ECM to the generator on channel 1 is square
wave/pulse width modulation signal/LIN line; the feedback signal of the generator on channel 2 is square
wave/pulse width modulation signal, which is displayed on channel 3. Is the output current of the generator.
Use the VATO oscilloscope to test the Focus smart generator, the specific operation is shown in Figure 3-5:
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Figure 3-5 Ford Focus Smart Generator
3.1.5 12V Start
Use the VATO oscilloscope to test the start of the gasoline car, the purpose is to test whether the performance of the
battery is maintained in the normal range. Use a BNC to banana cable, connect one end to channel 1 of the
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oscilloscope, and use two large alligator clips to clamp the positive and negative poles of the battery (the red wire
connects to the red clamp to the positive pole, and the black wire to the black clamp to the negative pole). Use a
current clamp above 600A, connect the BNC of the current clamp to channel 2, turn on the switch of the current
clamp, and clamp the current clamp to the positive or negative power line of the battery. You need to clamp the
entire positive or negative line. Stay, pay attention to the positive and negative polarity (positive current flows from
the positive to the negative of the battery). The specific operation is shown in Figure 3-6:
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Figure 3-6 12V Start
The following figure is the actual measurement diagram of the starting voltage and current of Mazda in a certain
year:
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Figure 3-7 Starting voltage and current
3.1.6 24V Start
Use the VATO oscilloscope to test the starting process of the diesel vehicle, the purpose is to test whether the
performance of the battery is maintained in the normal range, the operation process is the same as the 12V start. The
specific operation is shown in Figure 3-8:
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Figure 3-8 24V Start
3.1.7 Cranking Current
Use VATO oscilloscope with a current probe to conduct a current test on the starting process of the car (automobile
or diesel car), observe whether the current waveform is normal, use a current clamp of 600A or above, and connect
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the BNC of the current clamp to channel 2. On, turn on the switch of the current clamp and clamp the current clamp
to the positive or negative power line of the battery. You need to clamp the entire positive or negative line. Pay
attention to the positive and negative polarity (positive current flows from the positive electrode of the battery to the
negative electrode).
The specific operation is shown in Figure 3-9:
Figure 3-9 Cranking Current
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3.2 Sensor Tests
The sensor is an electronic signal conversion device that converts non-electrical information into voltage signals
and reports various information about changes in the working environment to the car computer. For example, the air
flow meter installed between the air filter and the throttle valve can measure the value of the air flow that is sucked
into the engine through the throttle valve. It converts the air flow value into a voltage signal and sends it to the
engine ECU (control computer), the control computer adjusts the corresponding fuel injection volume according to
the change of air flow to achieve the goal of the best combustion ratio. Another example is a vehicle speed sensor.
Its function is to convert the vehicle speed into a voltage signal and send it to the trip computer. The trip computer
controls the shift timing to achieve upshift or downshift.
With the continuous development of cars in the direction of intelligence and new energy, the number of sensors on
the car body has shown a trend of sharp increase, and there are nearly 100 sensors on the mid-to-high-end cars of
the company. The VATO series special oscilloscope can directly measure the signal waveform of the sensor. By
comparing with the standard waveform during normal operation, it is easy to find whether the sensor is normal. The
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VATO series oscilloscope can test the following types of sensors. The purpose is to compare the real-time
waveforms with the standard waveforms to help users find problems. The following are expanded and explained
separately:
3.2.1 ABS
The ABS wheel speed sensor is divided into analog and digital. The analog sensor has 2 signal terminals, the signal
is a sine wave, and the frequency of the sine wave represents the speed. Digital sensors generally have 3 terminals,
power, signal, and ground; the signal line needs to be tested, the signal is a square wave pulse, and the square wave
frequency represents the speed.
When testing, use BNC to banana cable, the BNC head is connected to the oscilloscope, and the banana head is
connected to the sensor or the ECM pin to test 1/2/4 signals at the same time. Shown as Figure 3-10:
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Figure 3-10 ABS Wheel Speed Sensor
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3.2.2 Accelerator pedal
The accelerator pedal is the signal of the automobile accelerator. There are generally 2 groups, each pair of 3 wires,
power, signal, and ground. Divided into analog/analog and analog/digital. Analog/analog signal is two analog
signals, usually there are two ways, one is deviation signal: one signal is from 0.3V→4.8V, which rises as the
accelerator pedal is depressed, and the other is 4.8V→0.3V, with Depress the accelerator pedal and descend. The
other is the same direction signal, but the voltage is different, one is 0.5V→2.5V, the other is 1V→4.5V; (the
voltage range is for reference only, the voltage range may be slightly different for different models, but the trend is
the same).
Use VATO oscilloscope to test the accelerator pedal sensor, the specific operation is shown in Figure 3-11:
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Figure 3-11 Accelerator Pedal
The following picture is the actual measurement diagram of the accelerator pedal sensor of a certain model:
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Figure 3-12 Actual measured waveform of accelerator pedal sensor
3.2.3 Air Flow Meter
Air flow meters generally have vane type, hot wire type, digital type, etc.; among them: vane type and hot wire type
are both analog output, and the output voltage is proportional to the air flow, generally 0.5V~4.5V, but the non-
linear ratio, It needs to be corrected in the ECM; the general output voltage is about 1V at idling speed, and the
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voltage rises rapidly during acceleration, reaching a voltage of 4V~4.5V. After stopping the acceleration, it will
return to the idling voltage; the output shows 0V or 5V is not normal.
The digital type has a digital circuit inside the sensor. The output signal is a square wave. The frequency is used to
represent the air flow. A higher frequency means a higher air intake. Use a BNC to banana cable and connect one
end to channel 1 of the oscilloscope. The black plug on the other end is grounded, and the red connector is
connected to the signal wire of the air flow sensor with a needle. Start the vehicle, quickly depress the accelerator
pedal and release it to test, you can view the waveform.
Use the VATO oscilloscope to test the throttle air flowmeter sensor (the air flowmeter is divided into three types:
analog, digital, and hot wire, please test according to different types), the specific operation is shown in Figure 3-
13:
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Figure 3-13 Air flow meter
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3.2.4 Camshaft
The camshaft sensor is generally used for timing, and is often tested in conjunction with the crankshaft sensor to
determine the timing of the vehicle. There are one or two camshaft sensors in the common car models, and the use
of four is relatively small. Common camshaft sensors are Hall type/induction type/AC excitation type;
Hall sensor output is square wave, high voltage can be 5V or 12V; generally 3-wire, power, signal, ground;
inductive sensor output is a sine wave signal or square wave signal, generally 2-wire; AC excitation The output of
the type sensor is multiple sine waves (there is a missing piece at the end of the camshaft, so that the signal
changes, and the position of the No. 1 cylinder is judged at the missing place), generally 2-wire.
Use a BNC to banana cable, connect one end to channel 1 of the oscilloscope, the other end of the black plug is
grounded, and the red connector uses a needle to connect the signal line of the camshaft sensor.
Shown in Figure 3-14:
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Figure 3-14 Camshaft
The following figure is the actual measurement diagram of the camshaft position sensor (Hall type) of a certain
model:
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Figure 3-15 Camshaft position sensor (Hall type)
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3.2.5 Coolant Temperature
The coolant temperature sensor is usually called a water temperature sensor. Generally, it contains a thermistor. As
the temperature increases, the resistance becomes smaller, which causes the output voltage to change, and the water
temperature changes slowly, so the voltage also changes slowly. Different models have different performances, and
the output voltage can increase with the water temperature, it can also decrease with the water temperature.
However, there is a special sensor called the Vauxhaus sensor. The output voltage of this sensor is 3-4V when the
vehicle is cold. As the vehicle starts, the temperature rises and the voltage gradually decreases. It is generally 1V
during normal operation, but as the vehicle temperature rises, when the vehicle temperature reaches 40-50 degrees,
the ECM will switch the voltage to make the sensor voltage rise rapidly to 3-4V, so as to achieve more accurate
voltage output at high temperatures.
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Use a BNC to banana cable, one end is connected to channel 1 of the oscilloscope, the other end is grounded with
the black plug, and the red connector is connected to the signal wire of the coolant sensor (the ground wire of the
coolant) with a needle probe.
Use VATO oscilloscope to test the coolant temperature sensor, the specific operation is shown in Figure 3-16:
Figure 3-16 Coolant Temperature
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3.2.6 Crankshaft
The crankshaft sensor is installed in many places, which can be near the front pulley or on the rear flywheel. The
ECM judges the precise position of the engine based on its output signal. Usually there are induction type and Hall
type: the induction type output is usually a sine wave, there are missing teeth on the disk, and the sine wave will be
missing in the missing teeth; this kind of sensor is generally 2-wire; the Hall type output is usually a square wave .
Generally 3-wire, power, signal, and ground. Use a BNC to banana cable, one end is connected to channel 1 of the
oscilloscope, the other end is grounded with the black plug, and the red connector is connected to the signal line of
the camshaft sensor with a needle.
Use the VATO oscilloscope to test the crankshaft position sensor, the specific operation is shown in Figure 3-17:
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Figure 3-17 Crankshaft position sensor
The figure below is the actual measurement of the crankshaft position sensor (inductive) of a certain model:
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Figure 3-18 Actual measurement diagram of crankshaft position sensor (inductive type)
3.2.7 Distributor
Distributor appears on models with high-voltage cables, and distribute the generated high voltages to spark plugs in
sequence. Distributors generally have Hall type and induction type. Hall type is generally 3-wire, voltage, signal,
and ground. The output is square wave. Inductive type is generally 2-wire. The output is sensing signal; use BNC to
banana cable, one end is connected to channel 1 of the oscilloscope, and the other end is black The plug is
grounded, and the red connector is connected to the signal line of the distributor with a needle.
Use the VATO oscilloscope to test the distributor sensor (divided into two types: Hall effect and induction). The
specific operation is shown in Figure 3-19:
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Figure 3-19 Distributor
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3.2.8 Fuel pressure
Fuel pressure signals generally appear on high-pressure fuel rails or sensors or common rail diesel vehicles, and the
pressure is relatively high. Generally, the fuel pressure is proportional to the output voltage, and the voltage
increases with the angle of the accelerator pedal (no-load and full-load will affect the voltage rise time).
Use a BNC to banana cable, connect one end to channel 1 of the oscilloscope, the other end of the black plug is
grounded, and the red connector uses a needle to connect the signal line of fuel pressure.
Use VATO oscilloscope to test the fuel pressure sensor, the specific operation is shown in Figure 3-20:
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Figure 3-20 Fuel Pressure Sensor Test
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3.2.9 Knock
The knock sensor is a passive device, generally 2-wire, signal and ground, no external power supply is required,
and a signal will be generated when it is subjected to vibration. It can also be removed for testing. The signal can be
generated by tapping, and the signal amplitude generally does not exceed 5V; if the sensor is removed and then
reinstalled, please be careful not to cause excessive torque to avoid damage to the sensor.
There may be several reasons for knocking: the ignition angle is too advanced, too much carbon deposits in the
combustion chamber, the engine temperature is too high, the air-fuel ratio is too lean, the fuel is not clean enough,
and the fuel octane number is too low.
Use a BNC to banana cable, connect one end to channel 1 of the oscilloscope, the other end of the black plug is
grounded, and the red connector is connected to the signal line of the knock sensor with a needle.
Use VATO oscilloscope to test the knock sensor, the specific operation is shown in Figure 3-21:
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Figure 3-21 Knock Sensor test
The following picture is the actual measurement diagram of the knock sensor of a certain model:
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Figure 3-22 Actual measurement chart of knock sensor
3.2.10 Lambda
The Lambda, or Oxygen Sensor is generally installed on the exhaust pipe, before the catalytic converter. It is a
feedback sensor used to sense the oxygen content in the exhaust gas, so that the ECM can judge the combustion
situation in the combustion chamber and adjust the fuel supply of the engine.
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There are several types of oxygen sensors: titanium oxygen, zirconium oxygen, and front & rear dual oxygen
sensors; the signal switching frequency is about 1 Hz, and it can only work when the temperature is normal. The
voltage is high when the mixture is thick, and the voltage is low when the mixture is thin.
Use a BNC to banana cable, one end is connected to channel 1 of the oscilloscope, the other end is grounded with
the black plug, and the red connector is connected to the signal line (pre-oxygen) of the oxygen sensor with a
needle. Use a BNC to banana cable, connect one end to channel 2 of the oscilloscope, ground the black plug on the
other end, and use a needle to connect the red connector to the signal line of the oxygen sensor (rear oxygen, if
there is no rear oxygen sensor, no test is required). If you want to measure current, connect the BNC end of the
current clamp to channel 3 of the oscilloscope, and clamp the clamp on the heating wire.
Use VATO oscilloscope to test the oxygen sensor, the specific operation is shown in Figure 3-23:
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Figure 3-23 Lambda (oxygen sensor) test
The following picture is the actual measurement diagram of a certain model of oxygen sensor:
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Figure 3-24 Lambda (Oxygen Sensor) diagram
3.2.11 MAP
The MAP, or Intake Pressure sensor is used to sense the pressure of the intake manifold and send it to the ECM to
determine the fuel supply, vacuum (or light load), and ignition timing advance angle. There are two kinds of analog
and digital, usually there are 3 wires, power, signal, ground, or together with other devices.
For the analog signal of a gasoline engine, when the throttle is closed or the engine is turned off, the output voltage
is 0, and the output is generally about 1V at idling speed (it may be slightly higher or lower). After quickly
depressing the accelerator, the throttle opens and the voltage rises rapidly. Achieve above 4.5V.
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For the analog signal of the diesel engine, the voltage is between 1.5-2.0V at idling speed. After stepping on the
accelerator, the voltage can be seen to rise, which can reach 4.0V.
Use VATO oscilloscope to test the intake pressure sensor, the specific operation is shown in Figure 3-25 below:
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Figure 3-25 MAP (intake pressure sensor)
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3.2.12 Road Speed
The speed sensor is generally installed on the drive output shaft of the speedometer of the gearbox or near the back
of the head of the speedometer, to provide information for the ECM and monitor power. Usually is Hall type, there
are 3 wires: power, signal, and ground, output square wave signal (some models will be analog, 2 wires, output
inductive signal, sine wave). Use a BNC to banana cable, connect one end to channel 1 of the oscilloscope, the
other end of the black plug is grounded, and the red connector is connected to the signal line of the vehicle speed
sensor with a needle. Lift the vehicle as a whole or lift the driving wheels or connect the signal to a road test, start
the vehicle, put in gear to rotate the wheels, and observe the waveform. The frequency of the square wave increases
with the increase of vehicle speed.
Use VATO oscilloscope to test the vehicle speed sensor, the specific operation is shown in Figure 3-26:
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Figure 3-26 Vehicle speed sensor test
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3.2.13 Throttle Position
The throttle position sensor is installed on the drive shaft of the throttle butterfly plate to sense the opening of the
throttle and provide a basis for ECM to judge the intake. There are analog output and throttle switch output.
Use a BNC to banana cable, connect one end to channel 1 of the oscilloscope, the other end of the black plug is
grounded, and the red connector uses a needle to connect the signal line of the throttle position sensor or the throttle
switch signal 1.
Use a BNC to banana cable, connect one end to channel 2 of the oscilloscope, the other end of the black plug is
grounded, and the red connector uses a needle to connect the signal line of the throttle position sensor, or the
throttle switch signal 2. (if it is a throttle switch, you need to connect this test lead).
Use VATO oscilloscope to test the vehicle speed sensor, the specific operation is shown in Figure 3-27:
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Figure 3-27 Throttle Position Sensor test
The following figure is the actual measurement diagram of the throttle position sensor of a certain model:
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Figure 3-28 Throttle Position Sensor Diagram
3.3 Actuators
3.3.1 Carbon canister solenoid valve
The carbon canister is generally installed in the engine compartment and connected to the fuel tank through a pipe
to collect the vaporized oil and gas in the fuel tank, so as to prevent the oil and gas from being discharged into the
air and causing pollution. Use a BNC to banana cable, one end is connected to channel 1 of the oscilloscope, the
other end of the black plug is grounded, and the red connector is connected to the ground wire of the canister
solenoid valve with a needle tip.
Use VATO oscilloscope to test the vehicle speed sensor, the specific operation is shown in Figure 3-29:
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Figure 3-29 Carbon canister solenoid valve test
The following figure is the actual measurement of the Carbon canister solenoid valve of a Audi A6 model in a
certain year:
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Figure 3-30 Audi A6 Carbon canister solenoid valve signal
3.3.2 Disel Glow Plugs
When the engine or the weather is relatively cold, it will affect the combustion of diesel fuel, so the glow plug is
required to heat the cylinder before starting. Diesel engine glow plugs generally have one for each cylinder,
connected in series, powered by a battery, and controlled by a relay to open and close.
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When the ambient temperature is low or the engine temperature is relatively low, when starting the vehicle, the
glow plug will be turned on first, and after the preheating light goes out, the vehicle can be started to make the
engine idling.
Use a current clamp, connect one end to channel 1 of the oscilloscope, and clamp the other end to the power cord of
the glow plug. Pay attention to the direction of the current.
VATO oscilloscope can be used to test the diesel engine glow plug (according to the type of glow plug, there are
two types: glow plug and single glow plug).
The specific operation is shown in Figure 3-31 below:
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Figure 3-31 Disel Glow Plugs
3.3.3 EGR Solenoid Valve
The EGR solenoid valve is an abandoned recirculation solenoid valve. After opening, a part of the exhaust gas will
be sucked into the intake manifold again to reduce the combustion temperature, so as to reduce the emission of
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nitrogen oxides in the exhaust gas and achieve the goal of environmental protection. Use a BNC to banana cable,
one end is connected to channel 1 of the oscilloscope, the other end is grounded with the black plug, and the red
connector is connected to the ground wire of the EGR solenoid valve with a needle.
Use VATO oscilloscope to test the EGR solenoid valve, the specific operation is shown in Figure 3-32:
Figure 3-32 EGR solenoid valve test
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3.3.4 Fuel Pump
The fuel in the fuel tank can be pumped and pressurized through the fuel pump, usually there are 6-8 sectors. Under
the same condition of the engine, a good fuel pump has the same and uniform current change in each sector.
Use a current clamp, connect one end to channel 1 of the oscilloscope, and clamp the other end to the power line of
the fuel pump. Pay attention to the direction of the current. (You can also use the corresponding fuse, replace it with
a extension cord and clamp on the cord of the current clamp).
Use VATO oscilloscope to test the electronic fuel pump, the specific operation is shown in Figure 3-33 below:
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Figure 3-33 Electronic fuel pump test
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3.3.5 Idle speed control valve
The idle speed control valve adjusts the throttle position or forms an air bypass around the engine according to the
load conditions of the engine and the engine temperature to deliver controllable airflow to the air duct to adjust the
engine idle speed. For gasoline vehicles, generally when the engine is cold started , The engine speed will rise
rapidly to about 1200 rpm. When the engine reaches the normal operating temperature, the idle speed will gradually
decrease, and finally stabilize at the preset value.
Use VATO oscilloscope to test the idle speed control valve, the specific operation is as shown in Figure 3-34:
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