Diodes are often parallel to other components so if one measures 'bad' it should be desoldered on one end and checked again. On the diode test position of most all digital meters, they will show between ~400- 900 depending on the type if the lead polarity biases them in the forward (conducting) direction. The indication isn't really too meaningful but roughly equates to millivolts of voltage drop in the forward (conducting) direction. Reversing the leads, especially on the diode range should just cause an over-range indication or the same as when the leads are not attached to anything. Shorting the leads should show very close to all zeroes.
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Diodes are often parallel to other components so if one measures 'bad' it should be desoldered on one end and checked again.
On the diode test position of most all digital meters, they will show between ~400- 900 depending on the type if the lead polarity biases them in the forward (conducting) direction. The indication isn't really too meaningful but roughly equates to millivolts of voltage drop in the forward (conducting) direction. Reversing the leads, especially on the diode range should just cause an over-range indication or the same as when the leads are not attached to anything. Shorting the leads should show very close to all zeroes.