2012 macbook pro hdmi to tv?

I also have a Sharp TV, which was working fine with my Macbook Pro and HDMI cable when I was running Lion, but as soon as I upgraded to Mountain Lion, it won't work at all. I've tried connecting to other TVs, some work, some don't. Anyone have fix?

I just tried connecting again for the 4 millionth time and it magically started working- I really didn't change any settings or anything, so I'm not sure why it finally decided to work. Sorry, this probably isn't very helpful, but I guess the only advice I have is keep trying?

ME too anyone noe how to fix it?? HELP!!! T_T

I have the same issue, with LIon on my MBP Retina the HDMI port worked fine, after the Mountain Lion upgrade it doesn't work. I upgraded one driver and I get an arrow on both screens (Mac and HDTV) and I can get a menu if I click two fingers but can't really do or see anythng else. I assume it is a software issue with Mountain Lion, but not sure.

Called Support today and tried many options. Mine would display in Safe Mode, so the tech had me try several things that made no difference. It has since been elevated to Engineerings where I could get a response in 2 days or after (Tech is off Tr and F). Supposed to hear back from him.

any luck? my second display says Not Support! or No Signal? on a blue screen. I can drag windows from the main desktop to the monitor, the MBP is recognizing but not displaying. In system pref, I have the mirroring options, Arrangement, etc???

After a week of back and forth with tech, it has been determined that it is a Mountain Lion issue as we have tried the follwoing. Reset PRAM, Checking extensions and LaunchAgents, re-installing Mnt. Lion, Clean install of Mtn. Lion. All the while HDMI port worked in Safe Mode, once it got to the login screen on the external display.

So with Screen Shots, capture Data and a few other pieces of information they gathered, it is back off to the engineering department. I may not hear until this weekend as the tech i have been dealing with has the next two days off, but he has been very good at trying to help, gathering info and working with me.

When I hear back and if there is a solution I will certainly pass it along here.

The HDMI port only seems to work if you are using the discrete video card, using the integrated video card == no go for hdmi. download gfxCardStatus to be able to switch between integrated and discrete cards. Using the integrated video will give you much better battery life! Hope that helps...

Alright, after talking with tech again and trying everything through the clean install, it still didn't work. It worked on an alternate TV (different Brand - Toshiba) with the same cord. The engineers think it has to do with Mountain Lion and support for Vizio TVs, they are looking into it internally and when they start to do updates to Mountain Lion that I should try at those junctures as they will add it to updates once it is figured out.

I tried the gfxCardStatus and that didn't work for me. Suggestion would be to try a different TV and see what you get (brand may not be setup right in Mt. Lion). So for now I wait.

My curiosity is if it is larger displays as my Vizio is 32 and the Toshiba is 19.

I have a 32" Panasonic TV, formerly working with Lion but, after the upgrade nada. The iMac sees the Panasonic in the Displays Preferences but, it won't transmit any sort of image or functionality over to it. I guess it's wait for an update and hope it is resolved.

Similar behavior with a Vizio 32" via mini-dvi-to-RGB connection (after upgrade to mountain lion); "Not Support" is displayed if I try with the macbook closed, but with it open, I can see the display just fine in dual-display mode.

Very bizarre...

Sad. I was so excited too.. it's definitely a bug of mountain lion.

Now, i wonder if anyone has tried doing it with VGA?

same problem here.

mac screen goes black when i connect the hdmi to a philips 1080p TV. the TV remains with no signal (blank).

the only thing you see is a big arrow.

sometimes part of the screen appears in a very low def. randomly.

i tried gfxCardStatus with all the possibilities, but nothing, it does not work.

everything after updating today the last .2 pack.

any news????

Exactly the same problem here.

MBP screen goes black when i connect the hdmi to a panasonic 1080p TV. The TV remains with no signal (blank).

The only thing you see is a big arrow on the MBP. The arrow looks normal on the HDTV.

I have a single pixel lit on my MBP.

It worked fine with Lion. Now it doesn't.

I have no Arrangement tab in Displays. (It might be there, but if it is it's on the phantom display to the right of my MBP which I think is there because the cursor seems to go off of the screen.)

A VGA Thunderbolt adapter worked fine last week. I reset my PRAM just in case some setting got stuck.