Two possible causes on these machines for your symptons.
Firstly, the machine may well be underfilling. This can cause the pressure sensor on the heater box not to be activated, so no heat. This is normally caused by a transfer hose in the front right of the machine silting up.
Secondly, a dry joint at the heater relay on the digiboard is a common occurence.
Other possibilities are heater failure, broken/damaged wiring in the door or temperature sensor failure – these are uncommon faults on this range.
If you’re going to have a peek, pull the plug first.
Regards,
Penguin45.