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AUTOOL DM303 Auto Diagnostic Multimeter User Manual 用户手册 www.autooltech.com...
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COPYRIGHT INFORMATION Copyright ● All rights reserved by AUTOOL TECH. CO., LTD. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of AUTOOL.
CAUTIONS Safe For the correct use of the instrument, please read the full text operation of this manual carefully before use, especially the “safety guidelines precautions”. The automobile diagnostic multimeter is designed and produced in strict accordance with GB4793.1 Safety Require- ments for Electronic Measuring instruments and IEC61010 Safety Standard, and conforms to double insulation, overvolt- standards...
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accuracy. Do not operate the instrument in the high temperature, high humidity environment. Especially, do not store the instrument in the wet environment, as the instrument performance may deteriorate if being wetted. Clean the instrument enclosure with a wet cloth and a gentle detergent, and do not use abrasive agents or solvents.
PRODUCT INTRODUCTION Overview ● The automobile diagnostic multimeter is a hand-held new diagnostic oscillometric multimeter integrating digital oscillo- scope, digital multimeter, automobile circuit and automobile signal inspection, which is designed with the embedded digital control technology. ● The multimeter mode can measure the AC / DC voltage and current, resistance, diode forward voltage drop, on-off and frequency.
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LCD is a 2.8-inch color screen, with a resolution of 320*240; ● ● Input impedance for the voltage measurement: it is 2~3MΩ when the voltage is lower than 160V; it is 10MΩ when the voltage is higher than 160V. The maximum input voltage is 1000Vpp;...
Button function Press for power-on, press for about 0.3 seconds to turn off the power when it is Power key on, and long press 3 seconds to reset the instrument. HOLD Pause Hold / Measurement key. Direction Select the functional items. button Return key.
Cable Cable Number number Distribution Name Functions Head No. DC connector, connected to the C01 - 1 battery clip line Terminals for C01 - 2 injector test and Automobile relay test C01 - K K line signal line Multi-functional detection line C01 - CAN+ CAN+ signal line C01 - CAN-...
OPERATIONS INSTRUCTION Functional ● The instrument is equipped with a power switch and the operation automatic sleep function. The automatic sleep time can be set guidelines to 1-30 minutes. The key tone of the instrument can be set to turn on and off, but the warning tone cannot be turned off. The brightness of the screen can be set.
Enter the function item, displayed as shown below: ● Voltage ( DC) 0.00V <HOLD>Hold <F1>Zero <Fn>Function Mode <F2>PULL DOWN ● The current measured value is displayed. If the voltage fluctu- ates, press the [HOLD] key to maintain the display status. If there is no voltage signal, the displayed value is non-zero, the red and black probe can be shorted, and press the [F1] key at the same time to perform the quick zeroing operation.
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Black ● Enter the function item, displayed as shown below: 5V/di v Trig. +00 U: 0.00V MIN: 0.00V MAX: 0.00V ● Display the current signal waveform, 5V/grid - display the voltage scale value, and press the [up] and [down] keys to change during measurement;...
In the process of voltage signal measurement, the instrument ● automatically changes the range and the maximum measur- able voltage signal is 1000V; Current ● Measure the current below 200mA, insert the red probe into measurement the green “mAuA” jack, and insert the black probe into the “COM”...
Press [F2] key and switch to detect high current mode as ● shown below: Ampere(DC) 10A(Yellow) 0.00A <HOLD>Hold <F1>Zero <Fn>Function Mode <F2>20A/mA In the high current mode, the maximum measurable current is ● 20A and the maximum measurable continuous current is 10A. There is 15A 30V self-recovery fuse inside, which can protect the instrument from damage due to excessive current in the use of vehicle detection.
Resistance 0.00Ω Diode: <HOLD>Hold <F1>Zero <Fn>Function Mode ● The instrument detection resistance and the diode are two-in-one function display. Press [Fn] key to switch the display mode. When measuring the resistance, the resistance can be set as the main display; when measuring the diode, the diode can be set as the main display;...
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C04 - 2 C04 - 1 Black Test signal ● Enter the function item, displayed as shown below: Voltage(DC) 0.00V Supply voltage: 12.50V <HOLD>Hold <F1>Zero <UP>SHORT TO B+ <DOWN>SHORT TO B- Connecting the battery for power supply, the instrument will ●...
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10K. If the circuit is insulated to ground, it indicates that the circuit has leakage, as shown in the following figure: Voltage(DC) 0.00V Supply voltage: 12.50V <HOLD>Hold <F1>Zero <UP>SHORT TO B+ <DOWN>SHORT TO B- ● If the detected voltage is very high and close to the power supply voltage, the instrument will display a number on the red background with a sound prompt, indicating that the circuit voltage is high, which may be a power supply line.
close to zero voltage, connect the probe to one line, press the up key of the instrument, and observe whether the lamp is on. If it is not on, replace it with another line. If the lamp is normal, one line will turn on the lamp when it is powered. If both lines cannot turn on the lamp when it is powered, the lamp is damaged.
CRANKING TEST CURRENT: 12.27V MINIMUM VOLTAGE: START 12.27V MIN VALUE > 9.6V PLEASE START THE ENGINE AND WAIT 15 SECONDS. At this point, start the engine and wait for 15 seconds, as ● shown below: CRANKING TEST CURRENT: 13.87V MINIMUM VOLTAGE: START 10.20V MIN VALUE >...
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C01 - 1 C01 - 2 Black Enter the function item, displayed as shown below: ● INJECTOR TEST SIMULATE ENGINE SPEED 1000 RPM PRESS <OK> TO OUTPUT <Fn> to signal check When first entering the function interface, there is no drive ●...
● Press [Fn] key to turn to the oscilloscope display mode, insert the red probe into V jack, and connect the injector pin with the red probe to observe the working waveform of the injection nozzle. At this time, the fuel injection drive and the oscillo- scope function are running simultaneously.
Enter the function item, displayed as shown below: ● RELAY TEST OUTPUT STATUS Contact Resistance: Ω PRESS <OK> TO OUTPUT Press [OK] to output the relay drive signal which is the same ● with the battery voltage. We can hear the relay on/off sound. When contacting the contact pin of automotive relay using the red and black probe, we can observe the resistance for the contact on/off and observe the conditions of relay.
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C01 - SIN C01 - 1 C01 - K C01 - S1 C01 - S2 Black Output signal: ● The “square wave” is identified as the signal line to output ● the 12V square wave signal. The “K-line” is identified as the signal line to output the 5V ●...
SINE/SQUARE WAVE OUTPUT frequency: 1000 Hz duty cycle: 50 % PRESS <OK> TO OUTPUT <Fn> to signal check (f<6000) <F1><F2> set duty cycle When you first enter the functional interface, there is no analog ● signal output. Press [OK] to output the signal. ●...
Enter the function item, displayed as shown below: ● 100uS 5V/di v 0 RPM 4STROKE SENSOR: Min: 0.00V Max: 0.00V Press [up / down] keys to adjust the waveform amplitude. ● ● Press [left / right] keys to adjust the time value. ●...
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C01 - K C01 - The instrument provides the detection capability of the 5V ● signal lines and the 12V signal lines. When connected to the 5V signal line, the signal on the K line is 5V signal, and when connected to the 12V signal line, the K line is 12V signal.
● Press the [left / right] keys in the receiving state to change the baud rate of communication. CAN bus data ● Insert the multi-function detection line into the multi-function interface (the top of the machine). The “CAN+” identification line connects the extension wire and probe; the “CAN -” identi- fication line connects the extension wire and probe;...
The measured signal frequency is 1Hz~1MHz. ● ● Enter the function item, displayed as shown below: FREQUENCY METER 50 Hz <Fn> to signal check ● It displays the frequency of currently detected. Due to the large input impedance of the instrument, the induced interference signal will be displayed when it is not connected to the signal to be measured.
MAINTENANCE SERVICE Our products are made of long-lasting and durable materials, and we insist on perfect production process. Each product leaves the factory after 35 procedures and 12 times of testing and inspec- tion work, which ensures that each product has excellent quality and performance.
Disclaimer All information, illustrations, and specifications contained in this manual, AUTOOL resumes the right of modify this manual and the machine itself with no prior notice. The physical appearance and color may differ from what is shown in the manual, please refer to the actual product.
RETURN & EXCHANGE SERVICE ● If you are an AUTOOL user and are not satisfied with the Return & AUTOOL products purchased from the online authorized Exchange shopping platform and offline authorized dealers, you can return the products within seven days from the date of receipt;...
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