Neff microwave oven won't stay on...

[chromey]

I've got a Neff B6774 microwave combination oven - almost 3 years old. The microwave won't stay on for longer than 3 seconds. It seems to trip-out. The problem started around the same time a rattling fan noise in the top of the oven - I've since fixed the fan noise but the microwave still wont stay on, in any setting, for more than about 3 secs. There is a mini fuse that's blown located on the circuit board but it's amps are not shown (M8/250G on the fuse). Appreciate any help...
Thanks.

 

[Leccy758]

Fuse amps does seem to be showing 8 @ 250V usually

This fuse sounds like the door interlock/low voltage side of the microwave circuit. Without looking I can not be certain

This can blow when the door interlock is broken or out of alignment in some way or when part of the microwave circuit itself (Transformer, HV Diodes, Capacitors, Magnetron) have failed. Not particularly easy to test and definately not for the home DIY'er (need to test for radiation leaks afterwards and some very high voltages stored).