Measuring Voltage (AC/DC)

• Used to check battery voltage in electronics and vehicles.

• Test wall socket voltage to ensure proper supply.

• Verify power supply output in electronic devices.

Measuring Current (AC/DC)

• Determine how much current flows through a circuit.

• Check for excessive current draw in appliances or automotive circuits.

• Monitor battery discharge or charging current.

Measuring Resistance (Ω)

• Test resistors to verify their values.

• Check for continuity in wires, fuses, or circuit connections.

• Identify open or short circuits.

Continuity Testing

• Quickly test if a wire or connection is intact.

• Emits a beep sound when the path is complete.

• Useful for checking cables, PCB tracks, and switches.

Diode Testing

• Measures the forward voltage drop of a diode.

• Ensures the diode allows current in only one direction.

• Helps identify faulty diodes in power supplies and rectifiers.

Capacitance Measurement (on advanced DMMs)

• Used to measure capacitor values.

• Helpful in troubleshooting power circuits and electronic boards.

Frequency Measurement (on advanced DMMs)

• Measures frequency of AC signals.

• Useful in testing oscillators, inverters, and power systems.

Temperature Measurement (with probe)

• Some DMMs allow temperature readings using a thermocouple probe.

• Applied in HVAC, refrigeration, and electronics testing.

Check Power Supply (Voltage Test)

• Measure voltage at the power source (battery, adapter, outlet).

• If there is no voltage, the problem is with the power supply.

Check Continuity (Broken Wires / Connections)

• Use continuity mode (beep test) to check if a wire, switch, or fuse is intact.

• If there’s no beep, the wire or component is open/broken.

Check Resistance (Component Testing)

• Measure resistor values to ensure they match their rating.

• High or infinite resistance may indicate a damaged component.

Check Current Flow

• Place the DMM in series with the circuit.

• If no current flows, a component may be faulty or the path is open.

Check Diodes and Transistors

• Use diode mode to test if a diode conducts in one direction only.

• For transistors, check junctions for correct forward/reverse bias readings.

Isolate the Fault

• Test one section of the circuit at a time (input, mid, output).

• Compare readings with expected values to locate the faulty part.