Im guessing that the clock is not flashing or lit?
In that case, seeing as nothing has been turned off, the most likely cause is going to be eithere abad connection to the cooker, or a bad main board.
Without a meter you wont be able to do much, sorry.
What you can try is, turning off the power to the oven, at the fuse box
Pull out the unit, and follow the cable into the cooker. There will be a removable cover.
Make sure that all the wiring is intact and tight.
If this does not solve the issue, I think you may have to get a hands on diagnosis as you dont have a meter.
If you want I can get you an all in quote for the repair, I just need the postcode.
In the meantime,
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