I've been working hard to find a Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.
I wonder whether you're ok with continuing to wait for an answer. If you are, please let me know and I will continue my search. If not, feel free to let me know and I will cancel this question for you.
Please note, I am just a moderator for this category, I can only try and find experts to help, I can't answer the question itself.
The answer would probably require someone to have the cooker workshop manual.
There is no rush, the cooker works without the timer and I will be away next week.
If the question is too difficult for the monies offered, please feel free to cancel the request.
It is a risk reduction question, I might just try prising a little harder (after the 20th August)
Thanks for trying
We will continue to look for a Professional to assist you.
If you decide on a refund, or wish to keep the credit for a future question, then of course we'd honour it.
Thank you for your patience,
Have you taken the appliance out of it's housing or are you trying to do this with it in situ?
in situ, its quite heavy to move out
I know it's heavy, it's a huge double oven unit.
Unfortunately, it has to come out to get to the screws holding the facia in place.
I have a portable table (adjustable height) that I slide the ovens out onto.
Once you have it out so you can work on it, and the power isolated.
Take the top panel off.
Take the screws holding the facia in place out.
Take the knobs and timer buttons off.
You can now take the facia panel off.
Check it out, see how you get on and get back to me.
Hope this helps
Thank you for your reply
I've moved my fingers over the top and behind and can't feel any screws.
The oven is indeed very heavy, and I think a very tight fit, with reasonable effort it does not want to move. Don't think I'll be moving it.
Is there any other way of confirming it is the timer display that has failed?
No, you have to take it out to access the wiring on the clock.
You'll need a multimeter to test the wiring and clock too.