External (thunderbolt) display not working at all when in clamshell mode

I am having a similar issue with the Thunderbolt Display not being activated when powering on my Mac. It does not register until after signing in on my Macbook Air. Also, the Magic Trackpad does not work very well.

This is really unlike Apple to release software before it is really ready. I hope they do not continue this trend of releasing on a specified date instead of delaying the release of a more stable, less buggy software update.

I Have the same problem. Thunderbolt Display not working anymore on my MacBook pro retina after uninstalled yosemite.

HI

I have two displays. After upgrading. I can't get the second one to work. And, mouse doesn't go back and forth between the mac book and the one display that is working.

I'm using a 2012 MBP w/Retina. My external display connected via thunderbolt-to-DVI adapter also stopped working when I installed Yosemite, but unlike several other people I have no trouble with my mouse cursor, boot times or other functionality.

I hope there's a fix soon!

Hmm

My MacBook Pro Retina 2013 is also having trouble.

I have a Thundernbolt display and a Dell 24inch display, each attached to a Thunderbolt port.

Under Mavericks and Lion this worked a treat.

Under Yosemite it is far more problematic.

If I reboot my MBPr with the Dell scree attached, both the Thunderbolt and Dell screen stay play, MBPr seen is vaguely lit but the login prompt/boot screen never appear.

If I disconnect the Dell external screen then the computer boots properly and the Thunderbolt screen lights up and this is where the boot screen/login screen appear which is correct.

This is a pain in the but.

I am also having strange and odd keyboard quirks under Yosemite (Bluetooth keyboard).

Also having Parallels issues and ChronoSync issues. :-(

Robin

After the Yosemite upgrade my external monitor won't work until after logging in, which is a real nuisance. Used to work fine before the upgrade. Can't find a fix, grrrr.

I am experiencing something a little different since upgrading to Yosemite.

More irritating than anything. when waking up from sleep while in clamshell mode with my thunderbolt display connected. My wired keyboard is not recognized.

to correct and use the keyboard i have to unplug from the port it is in and put it into another port. Not sure if there is a hardware/firmware issue that will fix this. Looking now....

Same here - I upgraded a few days ago and my external Thunderbolt display connected to my late 2013 MBP 15' suddenly stopped working today (an Eizo Coloredge) after a restart.

So annoying. It doesn't show up in system profiler at all and the Coloredge resolutely says 'no signal'. However, when unplugging the Thunderbolt cable, the Retina screen does flicker, resize, flicker again and then reverts to 'normal'. Have done multiple restarts, tried other Thunderbolt cables, ports, you name it. All was fine pre Yosemite.

Grrrrrr. Another bug.

I'm chiming in to add some weight to this thread. I know Apple never responds here but hopefully someone there keeps an eye out for patterns in threads. I have a MacBook Pro (Retina, Mid 2012) connected to a Thunderbolt display. Everything worked fine prior to Yosemite upgrade. Now, if I boot my computer with the display connected, it works fine. However, if I disconnect and reconnect, I can't get the external display to come on. Hopefully someone will find a workaround for this as I hate waiting for Apple's next release HOPING that they noticed and fixed this bug.

Just to add these tales of woe.

Under Yosemite my macbook pro won't talk to my external monitor Acer V223w.

After much experimentation and $#%@* language I discovered the following works (sometimes).

Plug everything in, turn monitor off, turn it back on again, unplug the DVI cable from the DVI-to-thunderbolt adapter.

(Thunderbolt end of the cable is still plugged in), then plug the DVI cable back into the DVI-to-thunderbolt adapter.

Then the Mac and monitor recognize each other. (Sometimes I have to do this a couple times.)

I've tried it with multiple cables, multiple adapters, etc.

Why this crazy bit of voodoo would work is anyone's guess. Apple - QA - please test with a bunch of

monitors. I know you can afford it.

I have a 2013 retina pro as well and I'm not having any issues using my dad's old 19" Dell Monitor. My advice, check your display and energy saver preferences. I would also advise all of you to reset the SMC and PRAM (just google how to reset them) and to repair your hard drive using disk utility while in recovery mode (google how to do that as well). The only problem I have while using my pro as a desktop with external monitor is it has to be plugged in or else it will go to sleep, even if my bluetooth keyboard and mouse are connected and working.

I'm experiencing the same thing. Have you found a fix yet?!

Ran Etrecheck and my results are:

Problem description:

Thunderbolt Display doesn’t come on after power up. Also my desktop picture gets changed after display is restored.

EtreCheck version: 2.1.5 (108)

Report generated December 31, 2014 at 10:08:41 AM CST

Click the [Support] links for help with non-Apple products.

Click the [Details] links for more information about that line.

Click the [Adware] links for help removing adware.

Hardware Information: ℹ️

MacBook Pro (Retina, 15-inch, Early 2013) (Verified)

MacBook Pro - model: MacBookPro10,1

1 2.7 GHz Intel Core i7 CPU: 4-core

16 GB RAM Not upgradeable

BANK 0/DIMM0

8 GB DDR3 1600 MHz ok

BANK 1/DIMM0

8 GB DDR3 1600 MHz ok

Bluetooth: Good - Handoff/Airdrop2 supported

Wireless: en0: 802.11 a/b/g/n

Video Information: ℹ️

Intel HD Graphics 4000

NVIDIA GeForce GT 650M - VRAM: 1024 MB

Thunderbolt Display 2560 x 1440

System Software: ℹ️

OS X 10.10.1 (14B25) - Uptime: 0:6:14

Disk Information: ℹ️

APPLE SSD SD512E disk0 : (500.28 GB)

EFI (disk0s1) <not mounted> : 210 MB

Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB

Macintosh HD (disk2) / : 499.07 GB (357.63 GB free)

Encrypted AES-XTS Unlocked

Core Storage: disk0s2 499.42 GB Online

ST1000LM024 HN-M101MBB disk1 : (1 TB)

THERESA EXT (disk1s1) /Volumes/THERESA EXT : 190.04 GB (189.34 GB free)

1TB External (disk1s2) /Volumes/1TB External : 810.17 GB (120.69 GB free)

USB Information: ℹ️

Apple Inc. FaceTime HD Camera (Built-in)

Apple Inc. Apple Internal Keyboard / Trackpad

Apple Inc. BRCM20702 Hub

Apple Inc. Bluetooth USB Host Controller

Apple Inc. MacBook Air SuperDrive

C-Media Electronics Inc. BassJump Core

Apple Inc. Apple Thunderbolt Display

Apple Inc. FaceTime HD Camera (Display)

Apple Inc. Display Audio

Firewire Information: ℹ️

LaCie Rugged FW/USB 800mbit - 800mbit max

disk3s1 (disk3s1) <not mounted> : 32 KB

320GB External (disk3s3) /Volumes/320GB External : 499.97 GB (88.33 GB free)

Thunderbolt Information: ℹ️

Apple Inc. thunderbolt_bus

Apple Inc. Thunderbolt Display

G-Technology G-RAID with Thunderbolt

LaCie Rugged mini

Gatekeeper: ℹ️

Mac App Store and identified developers

Kernel Extensions: ℹ️

/System/Library/Extensions

[loaded] com.Leawo.driver.AudioDevice (1.0.0d1 - SDK 10.2) [Support]

[not loaded] com.palm.ClassicNotSeizeDriver (3.2.1) [Support]

[not loaded] com.sierrawireless.driver.SierraDevSupport (2.0.4) [Support]

[not loaded] com.sierrawireless.driver.SierraFSCSupport (2.0.4) [Support]

[not loaded] com.sierrawireless.driver.SierraODSupport (2.0.5) [Support]

[loaded] com.sierrawireless.driver.SierraSerial (1.0.1) [Support]

[not loaded] com.sierrawireless.driver.SierraSupport (1.4.5) [Support]

[not loaded] com.sierrawireless.driver.SierraSupportKicker (1.4.5) [Support]

[not loaded] com.sierrawireless.driver.SierraSwitch (1.2.0) [Support]

[not loaded] com.twelvesouth.driver.BassJumpOverrideDriver (2.5.1 - SDK 10.9) [Support]

Launch Agents: ℹ️

[running] com.flipvideo.FlipShare.AutoRun.plist [Support]

[loaded] com.oracle.java.Java-Updater.plist [Support]

[running] com.twelvesouth.bassjump.observer.plist [Support]

Launch Daemons: ℹ️

[loaded] com.adobe.fpsaud.plist [Support]

[not loaded] com.gopro.stereomodestatus.plist [Support]

[loaded] com.macpaw.CleanMyMac2.Agent.plist [Support]

[loaded] com.microsoft.office.licensing.helper.plist [Support]

[loaded] com.oracle.java.Helper-Tool.plist [Support]

[loaded] com.oracle.java.JavaUpdateHelper.plist [Support]

[not loaded] com.sierrawireless.SierraReset.plist [Support]

[running] com.sierrawireless.SierraSerial.plist [Support]

[running] com.sierrawireless.SWoCMon.plist [Support]

[running] com.twelvesouth.bassjump.player.plist [Support]

User Launch Agents: ℹ️

[loaded] com.adobe.ARM.[...].plist [Support]

[loaded] com.google.keystone.agent.plist [Support]

[not loaded] com.macpaw.CleanMyMac.helperTool.plist [Support]

[not loaded] com.macpaw.CleanMyMac.trashSizeWatcher.plist [Support]

[loaded] com.macpaw.CleanMyMac2Helper.diskSpaceWatcher.plist [Support]

[loaded] com.macpaw.CleanMyMac2Helper.scheduledScan.plist [Support]

[loaded] com.macpaw.CleanMyMac2Helper.trashWatcher.plist [Support]

User Login Items: ℹ️

GrowlHelperApp Application (/Library/PreferencePanes/Growl.prefPane/Contents/Resources/GrowlHelperApp.app)

Suitcase Fusion Application (/Applications/Extensis Suitcase Fusion/Suitcase Fusion.app)

AdobeResourceSynchronizer ApplicationHidden (/Applications/Adobe Acrobat 8 Professional/Adobe Acrobat Professional.app/Contents/Support/AdobeResourceSynchronizer.app)

Dropbox Application (/Applications/Dropbox.app)

Google Drive Application (/Applications/Google Drive.app)

AirPlayitServerManager Application (/Applications/AirPlayit.app/Contents/Resources/AirPlayitServerManager.app)

Internet Plug-ins: ℹ️

Google Earth Web Plug-in: Version: 6.0 [Support]

Default Browser: Version: 600 - SDK 10.10

Flip4Mac WMV Plugin: Version: 3.2.0.16 - SDK 10.8 [Support]

RealPlayer Plugin: Version: Unknown [Support]

Silverlight: Version: 5.1.30514.0 - SDK 10.6 [Support]

FlashPlayer-10.6: Version: 16.0.0.235 - SDK 10.6 [Support]

WidevineMediaOptimizer: Version: 6.0.0.12757 - SDK 10.7 [Support]

Flash Player: Version: 16.0.0.235 - SDK 10.6 [Support]

QuickTime Plugin: Version: 7.7.3

iPhotoPhotocast: Version: 7.0

SharePointBrowserPlugin: Version: 14.4.7 - SDK 10.6 [Support]

AdobePDFViewer: Version: 10.1.0 [Support]

JavaAppletPlugin: Version: Java 7 Update 71 Check version

User internet Plug-ins: ℹ️

BrowserPlus_2.9.8: Version: 2.9.8 [Support]

fbplugin_1_0_3: Version: Unknown [Support]

Safari Extensions: ℹ️

Facebook Cleaner [Installed]

F.B. Purity - Cleans Up Facebook [Installed]

AVG Do Not Track [Installed]

3rd Party Preference Panes: ℹ️

3ivx MPEG-4 [Support]

BrowserPlus [Support]

Flash Player [Support]

Flip4Mac WMV [Support]

GoPro [Support]

Growl [Support]

Java [Support]

Tuxera NTFS [Support]

Time Machine: ℹ️

Skip System Files: NO

Mobile backups: OFF

Auto backup: YES

Volumes being backed up:

Macintosh HD: Disk size: 499.07 GB Disk used: 141.44 GB

Destinations:

Data [Network]

Total size: 3.00 TB

Total number of backups: 30

Oldest backup: 2014-07-08 04:52:19 +0000

Last backup: 2014-12-31 02:32:04 +0000

Size of backup disk: Excellent

Backup size 3.00 TB > (Disk size 499.07 GB X 3)

Top Processes by CPU: ℹ️

4% WindowServer

0% fontd

0% SystemUIServer

0% AppleSpell

0% Google Drive

Top Processes by Memory: ℹ️

309 MB mds_stores

241 MB Dock

206 MB com.apple.WebKit.WebContent

103 MB Safari

103 MB Google Drive

Virtual Memory Information: ℹ️

12.03 GB Free RAM

2.51 GB Active RAM

1.42 GB Inactive RAM

1.22 GB Wired RAM

2.03 GB Page-ins

0 B Page-outs

Diagnostics Information: ℹ️

Dec 31, 2014, 10:03:01 AM Self test - passed

Dec 30, 2014, 05:26:28 PM /Users/[redacted]/Library/Logs/DiagnosticReports/garcon_2014-12-30-172628_[reda cted].crash

If there's anyone out there that can help please...

I am running the latest firmware on the TBD and all software is up to date as you can see.

i been hearing a lot of reports of people using external monitors and other stuff not working anymore, so i pretty sure it has something to do with the new yosemite os.... so i am going to play it safe and stick with mavericks osx... its been working fine on my old acer monitor connected via "hdmi to vga" conversion wire thats also an "active" wire meaning it has a chip built in the wire to upscale or downscale the screen automatically as it needs to.

hope this helps. and Yosemite ***** btw.

I also have problems with my Macbook Air when I plug it into an external display. It runs super slow like it doesn't have enough ram to process simple programs like google chrome. I have found a fix though. When you plug it into an external display, make sure that you don't close the monitor of the macbook itself. This has cleared up all my problems with connecting my mac to an external display. Even with OSX Yosemite!