M542 problems see pictures

[i2i]

it looks like a diode to me as well, put there to short the supply if you connect it wrong. If so you should be able to run the drive without it there, have you tried it.?

[Ricardoco]

it looks like a diode to me as well, put there to short the supply if you connect it wrong. If so you should be able to run the drive without it there, have you tried it.?

It reminds me of the old CB radios that had a reverse polarity diode on the back to protect the board, but more often then not it used to blow the output transistor on the final stage as well anyhow.. Rick