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giannisg Author

Level 1

5 points

my macbook pro does not detect external display anymore

i bought a new plasma panasonic tv one month ago and i have the adapter and everything.... i've also watched already over 30 movies by connecting my laptop with the tv through the adapter and hdmi cable... yesterday i was at a friends place and i connected my adapter to his hdmi cable and my mac detected his tv straight away but it didn't work . after this my friend told that he faced a problem with the hdmi cable(brand=hama) and he could not connect his laptop . after finding his tv and finally not working today i connect it to my own tv and the screen turns blue for a couple of seconds like trying to connect but does not detect my tv ... anybody has any idea what happened. my mini dvi port seems to work because the moment i connect the cable it turns blue( as when i was watching movies no problem)... now what happened ??

Message was edited by: giannisg

macbook pro 13,3 late 2010, Mac OS X (10.6.6), intel core 2 duo 2,4GHz , memory->4GB 1067 DDR3

Posted on Jan 23, 2011 9:01 PM

378 replies

ondramie

Level 1

4 points

May 17, 2016 1:29 PM in response to tapedoctor

My macbooks are:

(1) MacBook Pro (13-inch, Early 2011)

(2) MacBook Pro (13-inch, Early 2014)

My monitor is Asus PA246. (2) works and (1) doesn't. I have done the following:

(1) installed DisplayMenu and switched resolution

(2) reset PRAM

(3) installed gfxcardstatus and switched from dynamic to discrete, and vice versa

(4) toggle cables until my hands were chapped

Nothing works. Any additional suggestions?

Jul 18, 2016 11:08 PM in response to frodaddy00

OMG this was my problem. I am so thankful to you. I had to force it in there!

Nov 27, 2016 8:12 PM in response to giannisg

I had the same issue and tried everything without luck then I remembered that when I had a similar problem a couple of years ago I fixed it by doing a slightly different PRAM reset like this:

1) turn the computer off

2) Unplug the thunderbolt monitor

3) unplugging the magsafe

4) plug the magsafe in again

And then and this is important:

5) hold the option-command-"R"-"P" and then the power button and WAIT FOR THE START CHIME TWICE before releasing all the keys and then wait for it to chime again while it restarts.

6) after it restarts and after you login plug the thunderbolt monitor while the monitor is ON

7) wait for the content of the screen to transfer from the macbook to the to the external monitor

8) Close the macbook lid and wait for the monitor to flicker once.

Hope this helps. It helped mine and a friend's Macbook Pros that were not recognizing external monitors.

my macbook pro does not detect external display anymore