Re: smeg slim line dishwasher
If it is steaming, it is activating the heater, therefore it thinks it is already full of water. This indicates a failure in the water level control system.
The other possibility is that the circulation pump is not running; you should be able to hear it humming away after the fill sequence.
Either way, this is likely to be a technical repair, so perhaps a visit to Directories or Reairs@ ?
Power off if investigating further.
Regards,
Penguin45.