Hi,

Very often my display looks like this: http://pmrb.free.fr/n9-display/
That means black lines or sometimes a completely frozen screen.

It seems to happen more often, when it's cold.

I guess, that there is some defective contact, that would be perhaps not too much hard to repair. What do you think, do you have any experience with such a problem?

TIA for any hints, Peter

I haven't seen it on a phone just yet but I have seen similar effects on old laptops. The problem was always a faulty connection. Either a contact or a broken cable.

LE55ONS has a nice YouTube video tutorial about opening the N9. It might be worth trying to just unplug the display and plug it back in. If that does not help, the next thing to try is replacing the cable or the whole screen.

I had that on an E75 after I dropped it.
I was lucky and it is just a loose connection. In that case, watching the youtube video mentioned above will help you readjust the ribbon cable. Be extra carefull when you push back against the back of the screen to separate it from the phone housing.

I had that on an N9 with a replacement screen I bought off ebay, and unfortunately I had to order another replacement screen

So I hope you are lucky in this case!