Lens won't open at startup

Hello fellow fixers,

I've just bought this broken camera for 5 bucks, hoping I would fix it. But before I start tinkering, I thought I might ask it here first.

When I turn the camera on, the lens simply won't open. There is a buzzing noise for a good 5 seconds, then it stops and after that, nothing. The battery is completely charged.

How can I fix this?

Thanks in advance.

Nicolas