Good morning my name is ***** ***** I will assist with your query.
It sounds as though you have enabled the child lock on the oven itself.
On the bottom of page 3 of the manual here, it explains how to disabled the child lock.
1. Set the function knob on the left to off (0) and the temp control knob on the right to 0.
2. Press and hold both the OK button (which is directly left of the clock) and the - button (which is directly right of the clock) for about 5 seconds, the lock symbol should disappear.
Please let me know if this has resolved your issue.
Apologies for the delay in responding, I would look to switch the power to the oven off at the wall for 5 minutes, then switch it back on, press the ok button (left of the clock), and see if the oven starts working again. If it does its just a case of setting the time using the button to the right of the clock.
Carol, a new control board (PCB) would probably cost around £100 so about 130 Euro Carol, so its abit on the high side, but not far off when you factor in labour costs
This sounds like the timer within the PCB has failed again from what I can tell, if it was the child lock (and user error by your tenants) you would also see the letter LOC on the display but as its just the lock symbol it sounds like the PCB has failed again.
The part can be sourced here for example, I would call back the original engineer as the part must still be under warrenty, and ask them to replace the part free of charge, as the PCB's should last for 10 years plus, unless they are either second hand or incorrectly installed (without an anti static band).
If you are mechanically minded yes, its no harder than replacing a hard drive or ram chip in a computer, but alot more time consuming than changing the light bulb in the oven.
In essence the oven has to come out, the lid on top unscrewed, then the PCB unbolted\un-clipped and then the terminals disconnected.
The key here is if you had an engineer do it they can test the circuit with the multi meter to be sure thats defiantly the faulty part and its not a fault on the display for example. Personally if you can find someone to fit the part for 50-80 Euro I would go for that than the grief doing it yourself.
Please let me know if I can be of any further assistance, if not appreciate if you can rate the service received.
Do you need any further assistance with you query?
Good morning Carol, I havent heard from you in the last couple of days do you still require assistance. In order for me to close the case I need you to rate the service received using the star rating on this page.