Belling IDW604?

Still getting an E3 error code. (Heating element or heating sensor, or even worse, the control pcb). I have tried underloading it, which didn't seem to work. I have read that there is a reset switch under the door - anyone any ideas? 'Phoned up Belling helpline - fat lot of help they were although he said that he hadn't heard there is a reset switch.
I have heard of an instant fix though - a very large hammer and very indiscriminate use all over the pain in the a--e contraption!!!

Neil.