Use the following  with caution, you can seriously mess up your TV if you do not know what you are doing!! 
Consider yourself (and everybody else) warned!
Now proceed at your own risk.
When you have finished do not even consider phoning an injury claims lwyer 
Menu
Set Up press go
press 0 0 go
TV press go
Service counters press go
then press exit
 Llewelyn:
 Llewelyn:
Menu
Rewind, rewind, stop (on the beo4) and it is in that service menu under monitor information I believe.
 
 
Nice try Llewelyn, but I think  that is for entering the pin code menu 