Schreiber APM2222 cooker hood replacement or repair

This cooker hood in a rented property is so greased up even after cleaning the light switch turns on, the bulbs flicker then go off. Doesn’t blow the fuses. I assume the switch and connections are greased up inside. The fan works fine. Does anyone know if it is possible to dismantle, clean or replace the switch. If not, recommendation for an inexpensive replacement hood that will fit the gap as it is built in under a canopy. There are so many different types it is difficult to find out what a compatible replacement would be. If anyone knows this cooker hood APM2222 hopefully can advise.
Thanks