Overview 

The Autool DM303 Auto Diagnostic Multimeter is a versatile 4-in-1 automotive diagnostic tool that combines the functions of a digital multimeter, handheld oscilloscope, signal generator, and automotive circuit tester. It’s designed for 12V vehicle systems and is capable of measuring engine RPMs from 500 to 6000, testing ignition pulses, fuel injectors, and detecting signals from crankshaft and camshaft sensors. Featuring a 2.8-inch color display and true RMS auto-ranging capabilities, the DM303 provides accurate readings of voltage, current, resistance, and more. It can also simulate signals such as sine and square waves to test actuators and relays. With a compact design, multilingual interface, and a robust set of included accessories, it’s ideal for diagnosing complex vehicle electronic systems.

Features

• Combines multimeter, oscilloscope, signal generator, and circuit tester in one tool

• Supports 12V automotive systems with RPM detection from 500–6000 RPM

• Measures voltage, current, resistance, diodes, and continuity with True RMS accuracy

• Features a 2.8-inch color LCD with adjustable brightness for easy viewing

• Built-in handheld oscilloscope for waveform analysis of ignition, sensors, and CAN/K-line signals

• Tests fuel injectors and ignition pulses with real-time signal reading

• Outputs analog signals (sine/square waves) and 12V pulses to simulate actuators and relays

• Performs cranking battery voltage test to detect drops below 9.6V during engine start

• Supports multilingual menu (12 languages) for global usability

• Comes with a full accessory kit including test leads, battery clips, jump wires, and toolbox