M542 problems see pictures

[Swarfing]

Getting back to the task in hand, i had one (different model) that i acquired blown. It would not power up without the diode in place. This one could be different?

[i2i]

Getting back to the task in hand, i had one (different model) that i acquired blown. It would not power up without the diode in place. This one could be different?

if the diode is in series with the power lead it needs to be there to conect the circuit, but this one looks like it's across the supply.