MBP with external screen issue

[^squirrel^]

Hi,

My set up has been running fine for the last month and now it's playing up.

I run a Samsung 20" screen from my MBP set as mirroring. Connected to my laptop is the USB keyboard and mouse.

Normally when i close the lid the laptop sleeps, then i press any key and the machine wakes up and displays on the external screen.

Problem now is when the machine wakes up, it goes back to sleep within 3-5 seconds. When i eventually give up trying and open the laptop lid, it doesn't display a screen on the laptop, but it does on the external. So i have to reboot.

Can anyone help with this issue, as im sure this is happened before.

many thanks
Darren

 

[Vedhead]

I have that issue..but I think its only when the ol' MBP isn't plugged in.

Is yours unplugged?

Also, instead of a reboot, try going into Displays and hitting Detect Displays...that should find the MBP screen for a switch back...

 

[aristobrat]

I have that issue..but I think its only when the ol' MBP isn't plugged in.

Same here. Only happens when I forget to plug the power adapter into my MBP.

 

[^squirrel^]

Power is plugged in as always.

 

[DannySmurf]

Same here. Only happens when I forget to plug the power adapter into my MBP.

Had this problem with my first-gen MBP. If I start it running on battery with an external monitor, it goes into an "infinite sleep loop." I've just accepted it as a reality and make sure to plug my computer in before I started it up closed.

However, from the original poster's comments it doesn't sound like this is actually the problem; rather, that it was doing what he expected before, but now it's not. For that, I don't know of a solution (unless his power adapter has come unplugged and he just hasn't noticed).

 

[^squirrel^]

Just to update you with what i've tried.

I just tried it without the battery connected and still the same issue.