LED Cinema Display (24-inch, Late 2008): Intermittent flicker while connected to a Thunderbolt port
In certain cases you may notice an intermittent flicker on an Apple LED Cinema Display (24-inch, Late 2008) while it is connected to a Thunderbolt-enabled Mac.
|Do install this firmware update if:||Do NOT install this update if:|
|Your 24-inch LED Cinema Display flickers while connected to a Thunderbolt-enabled Mac.||You do not experience a flicker.|
|You do not need to use a display extension cable.||You use an extension cable.|
If you need assistance determining if you should install this update, contact AppleCare for support.
Preparing for installation
- Connect your Thunderbolt-enabled Mac to a working power source.
- Connect both the display cable and the USB cable from only one Apple LED Cinema Display (24-inch, Late 2008) to your Thunderbolt-enabled Mac.
- Make sure there are no display extension cables connected between your display and your Mac.
- Disconnect all nonessential devices from the FireWire and USB ports, and use only an Apple keyboard and mouse to apply the update.
- Quit all applications.
Downloading and installing the update
- Download the 24-inch LED Cinema Display Update.
- Double-click the "24-inch LED Cinema Display Firmware Update" to mount the disk image.
- In the mounted disk image, double-click the "24inchLEDCinemaDisplayFWupdate.pkg" package to install the firmware updater application in your /Applications/Utilities folder.
- If installation of the firmware updater is successful, the updater should run automatically. You can also start the updater manually from the /Applications/Utilities folder.
- A window appears. If a message appears that says "No device was detected. If you have a device in need of updating, verify it is attached and has power," verify that both the display cable and the USB cable are connected. If they are, this update is not intended for your display. Quit the application.
- Click Update to install the firmware.
- Enter the administrative password for your computer at the prompt. Click OK. When the update starts, the status bar in the Firmware Update window indicates the progress of the update.
- When installation is complete, the message "This device is up to date" appears, confirming the update was successful.
- Click OK and quit the firmware update application.
- Unplug the display's AC power cord for fifteen seconds, then plug it in again to complete the process.
- Do not interrupt the update. Make sure the USB and Mini DisplayPort cables you use to attach your 24-inch LED Cinema Display to your Thunderbolt-enabled Mac remain connected for the entire process.
- Some features of the display will not function while the update is running.
- If the display remains blank for more than 30 seconds, unplug the display's AC power cord for 15 seconds and then plug it in again to complete the process.
- If the update does not install, quit the application, unplug the display's AC power cord for 15 seconds, then plug it in again. Run the firmware update again.
To verify that the LED Cinema Display (24-inch, Late 2008) firmware update has been applied successfully, note whether the message "This device is up to date" appears. Unplug the display's AC power cord for fifteen seconds, then plug it in again before confirming that the display flickering no longer occurs.
If display flickering continues after applying the firmware update or if you have any questions or other issues, contact AppleCare for support.
For lab or institutional customers who have mixed deployments of Apple displays, it may be helpful to apply a small sticker (or similar) to indicate that the LED Cinema Display (24-inch, Late 2008) has updated firmware; firmware update information is not easily available via System Information or System Profiler.