What should a good diode read when tested with a digital multimeter on the diode check position?

When testing a good diode with a digital multimeter in the diode check position, you should expect to see a forward voltage drop reading, which typically falls within a range of about 0.6 to 0.7 volts for silicon diodes. The reading from the multimeter indicates how much voltage is needed to allow current to flow through the diode in the forward direction.

In this context, a reading of approximately 0.551 volts when forward-biased, followed by an 'OL' (over limit) reading in the reverse polarity direction, indicates that the diode is functioning properly. The 'OL' signifies that the diode is not allowing current to flow in the reverse direction, which is an essential characteristic of a diode. It allows current to pass in one direction while blocking it in the opposite direction.

The other options do not reflect the expected behavior of a functioning diode. A reading of 'OL / OL' would suggest that the diode is entirely non-conductive in both directions, which is not typical for a good diode. A symmetrical reading like '300 / 300' may indicate a short or incorrect setting on the multimeter. A reading of '0.475 / 0.475' might imply a forward drop that is