Advent 7104 wont start up

[Anna R]

Hi

Ive had this before but cant remember how to fix it. I left my Advent 7104 on and when I came back to it, it had shut itself down. On pressing the power on button nothing happens except the red power light flashes 3 times.

Ive tried the usual, disconnecting the battery and/or power supply but nothing helps. Any ideas?
Thanks

 

[huggie54]

have you tried running on mains without the battery

 

[Anna R]

yeah, still the same