If none of the troubleshooting methods worked above, it is recommended that you contact Apple Support by calling 1-800-MY-APPLE, scheduling a Genius Bar appointment or choosing another option. If this resolves the issue, then possibly your Thunderbolt Display's dual MagSafe-Thunderbolt cable is damaged. Try connecting a standalone Thunderbolt cable between your Mac and Thunderbolt Display. Hold these keys until the Mac restarts and you hear the startup sound for a second time.Īfter resetting NVRAM, you may need to reconfigure the Mac's settings for speaker volume, screen resolution, startup disk selection, and time zone information.Press and hold the Command-Option-P-R keys immediately after you hear the startup sound.NVRAM, short for 'non-volatile random-access memory,' stores certain settings even when your Intel-based Mac is turned off. On Macs with MagSafe power adapters, the cable's LED might change states or temporarily turn off when you reset the SMC. Press the power button to turn on the Mac.Īpple provides steps for Macs with removable batteries, and the Mac Pro, iMac and Mac mini, on its support website.Release all the keys and the power button at the same time.On the Mac's built-in keyboard, press the left side Shift-Control-Option keys and the power button simultaneously.Plug in a MagSafe or USB-C power adapter to a power source and to your computer.These instructions are for Mac notebooks with non-removable batteries. Intel-based Macs have a System Management Controller (SMC) that can be reset as a possible fix for Thunderbolt Display issues. Wait at least 30 seconds before powering on your Mac and Thunderbolt Display.Disconnect all USB peripherals and any cables plugged into the Thunderbolt Display.Disconnect the Thunderbolt Display from AC power by unplugging the cord.Disconnect the Thunderbolt Display's MagSafe cable from your Mac.Shut down and disconnect both your Mac and Thunderbolt Display from AC power for at least 30 seconds. Click on the Update button next to the latest OS X version in the Mac App Store.Click on About This Mac in the dropdown menu.Click on the Apple logo in the top-left menu bar.Before contacting Apple, follow these troubleshooting steps to see if you can reset your Thunderbolt Display.Īs a preliminary measure, it is recommended that you update your Mac to the latest version of OS X. In many cases, the display is not broken. Apple's Thunderbolt Display, for myriad reasons, may not display an image from your Mac, recognize USB peripherals, connect to Ethernet, or power on whatsoever.

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