Which symbol should you use on the dial switch to measure diodes?

• A. |
• B. >|
• C. -|
• D. ->I-

Answer: (D)

The key idea here is to use the meter’s diode test function. When you measure a diode, you want the instrument to apply a small, controlled current and read the forward voltage drop, while also letting you check reverse blocking. The symbol that indicates diode testing on the dial is the one that resembles the diode schematic (the symbol that looks like a diode with a line), which is specifically designed to engage the diode-test circuit. This mode gives meaningful results for diodes: a forward drop in one direction (typical around 0.6–0.7 V for silicon, lower for Schottky) and little to no conduction in the reverse direction. Other symbols correspond to resistance, continuity, voltage, or current modes and won’t provide the correct diode behavior. That’s why this symbol is the correct choice for measuring diodes.