Symptom
On some Apple flat-panel displays, the power light can display a series of short flashes when an error has been detected.
Products Affected
- Apple Studio Display (15-inch flat panel)
- Apple Studio Display (17-inch flat panel)
- Apple Cinema Display (20-inch flat panel)
- Apple Cinema Display (22-inch flat panel)
- Apple Cinema HD Display (23-inch flat panel)
Solution- If you see a repeating sequence of three short flashes, the monitor is detecting input in the wrong video format. Check that your monitor is compatible with your graphics card and that you've installed the correct display software, if your monitor came with installation software.
- If you see a sequence of two short flashes and a long flash, the monitor is detecting a problem with a backlighting lamp. Contact an Apple-authorized dealer or service provider.