How to Test Electrical Components With a Multimeter
- 1). Set the multimeter for the component you want to test or read. For example, to check connectivity, diodes or transistors, set the multimeter to ohms.
- 2). Connect the terminals. Connect the positive terminal of the multimeter to the portion of the component that should have a positive charge, and connect the negative terminal of the multimeter to the portion of the component that should have a negative charge.
- 3). Read the multimeter. A diode should produce a low to medium reading. A transistor should result in an "open circuit" reading. If you test voltage, the reading will display a number of volts. If you receive a negative reading, try reversing the positions of the positive and negative terminals and reading the multimeter again.
- 4). Repeat your test on a transistor with the positive terminal connected to the base and the negative terminal connected to the emitter. Read the multimeter to ensure you still have an "open circuit" reading.
- 5). Reverse the connections to test a diode or transistor. For a diode, connect the negative terminal to the cathode and the positive terminal to the anode. A high resistance reading should result. For a transistor, connect the negative terminal to the transistor's base and the positive terminal first to the collector and then to the emitter. In both cases, you should get an "open circuit" reading again.
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