Grandma and her MOBILE PHONE

Not long ago, my grandma called back to our hometown.
With a phone that she used for a couple years, and it obviously has lots of problems.

But my grandma don't wanna change her old phone.
The phone always shut down by itself, when she wants to on again, it required to key in PIN code.

It happened just now..
And so..

We asked whether what's the code to access to her phone, and she said she don't know!!

But..

After few second, I heard the sound of phone starting up!
'What code? Why want codes? I don't know about code but I know how to press.'

Miracle! She don't know the codes but how she switch on the phone?

After her call done, the phone shut down again.
'See by yourself, 'die' again lah!!!' she said.