8310 switching on and off every 5 secs

[odonaghue]

Hi i have an 8310 and when you switch it on, it will stay on for 5 secs then switch off, stay off for 5 secs, then switch back on - and so on. But when i remove the sim it will stay on all the time. I left it in a nokia centre and the guy changed the battery and the battery connector but it's still doing the same thing. I checked the battery connector and it doesn't look like it was changed at all, it looks like nokia centre man ripped me off. I tried a new screen and flashed the phone but no luck..... So if anyone has any ideas at all it would be great.