Vitrifrigo fridge won't turn off - even when switch is set to off!

[Qfirebird]

Hi all, first time poster. We have a second hand well worn bongo friendee from 1998 with existing conversion and habitation upgrades. Been steadily getting things fixed and cleaned and replaced.

Was planning to go out after a vendor provided us a hab check and confirmed that all parts were working, I tested the fridge (no label or serial no visible without removing parts) today and after letting it cool a bit I was satisfied, turned the switch off and.. compressor kept going. After pulling my hair out trying to get the switch to work, and pulling likely fuses from the control panel from other threads online's advice, the thing is still going.
I'm not very mechanically minded but I don't want this thing to be going all day and night and draining the leisure battery!

Pictures to follow. I just don't know what to do! Feel at our wits end with this additional to faulty pump, rust marks and holes.. did we take on too much of a project for complete amateurs?

[g8dhe]

Which switch are you referring to, to turn it off?
There is a knob inside, but no On/Off switch on the Vitrifrigo's I've seen, there has always been a separate switch on a 12v control panel (often far right switch for Ancillaries) that controls the fridge.
Really need pictures of conversions and added equipment as there are so many possibilities and configurations which make each van unique.