I’ve never heard of any oven failing but ours went bang after my wife opened the door.
Following that, the residual current device (RCD) circuit breaker would trip as soon as the left knob was turned to any position other than Off or Light (even with the temperature down at 0).
To take it apart, first you release the door by pushing down on the little tabs on each side.
Then there are two little self-tapping screws in the left and rightmost black plastic coverings that screw it into the recess.
After that the oven comes straight out. It’s not too heavy, maybe about 10 kgs.
All the remaining screws are Torx (and the same size). Following the power cable, the top part looks fine.
In the bottom section one can see the connections to the top heating element. They looked ok as well and resistance was fine between the elements and to ground..
The four terminals at the bottom are those for the bottom element. The black one (second from the left) had low resistance to earth so I unplugged them and the oven stopped tripping the RCD.
This is the bottom element. Notice the insulation of the second terminal is charred. That must be the problem!
The Miele part number is 5001061. Of course, they don’t make the oven any more. There was a second hand one on ebay and they’re available at https://www.statewideapp.com.au/miele-oven-bottom-element-550560w-5001061 for $175.96 + $15 shipping (which I ordered).
13/12/2021 - the part finally arrived. Pleased it’s the right one.
Oven as good as new!
18/12/2021 - finally got a quote from Miele Australia for $156.50.