MacBook screen black, flickering or with lines: causes

A screen that stays black, flickers or shows lines is hard to interpret on a MacBook: it can be the software, the backlight, the cable to the screen or the screen itself. Fortunately a few simple tests quickly show where to look. They also tell you whether it is worth trying something yourself, or whether it is time for a repair.

Blue Apple repairs MacBook screens at Rijnstraat 76-H in Amsterdam. A cracked or damaged screen is covered in our article MacBook screen broken: first steps and options; this guide is about screens that show nothing or do strange things.

Three tests that make it clear quickly

1. Is the Mac actually on? Do you hear the startup sounds or the fan, does the keyboard light up, or does the Caps Lock key respond? Then the Mac is running and the problem is the screen or its backlight.
2. Connect an external monitor. Over HDMI or USB-c. If the picture appears there, the Mac itself works. That is good news for your data and points to the screen, the cable to the screen or the backlight.
3. Take a screenshot. Press Shift + Command + 3 and open the file. If you see the lines or the flicker in the image too, the problem is in software or the graphics chip. If the image is clean while the screen is distorted, it is in the screen or the cable.

A black screen while the Mac is on

• Torch test. Hold a torch at an angle against the screen. If you see a faint image, the panel still works but the backlight has failed.
• Brightness. Sometimes it is simply set to zero, or the Mac is asleep without the screen waking up. Try the brightness keys and close the lid for a few seconds.
• Restart. Hold the power button for ten seconds and start again. On an Intel Mac an NVRAM reset can sometimes help.
• Cable or backlight. If the external monitor works and the torch test shows a faint image, the cause is often the backlight or a cable in the hinge.

Flickering

• Does it flicker only on battery or in certain apps? That can be a setting, such as True Tone, automatic brightness or graphics switching.
• Does it change when you open or close the lid further? Then the cable in the hinge is often worn, because it bends with every movement.
• Is the bottom edge of the screen lighter, like lamps along the bottom? That is a known pattern on a number of MacBook Pro models from 2016 to 2018 and points to wear of that cable.

Lines, stains and bars

• Vertical or horizontal lines that also appear in a screenshot more often point to software or the graphics chip.
• Lines and stains that are not in the screenshot belong to the panel or the cable. An ink-like stain or dark patch is usually pressure damage, for example from a pen, earbuds or a webcam cover left between the screen and the keyboard when you closed the lid.
• A cracked back of the screen or a lid that sits crooked can point to a fall or a swollen battery: see when to replace a MacBook battery.

What replacing means

The screen of a MacBook is a complete part: panel, glass, backlight and cabling form one whole. A repair therefore usually means that whole is replaced. For some faults that is not needed, for example if only a cable or the backlight is the problem. Which qualities we offer and what the difference is you can read in our article on original or compatible MacBook screens, and per model on the MacBook screen repair page.

What we do at Blue Apple

We run the same tests as above, but with a test screen and measuring equipment. That tells us whether the panel, the cable, the backlight or the graphics chip is the cause, and lets us say honestly what a repair involves before anything is replaced.

Frequently asked questions

My screen is black but the Mac seems to work. Are my files safe?

Probably. If the picture appears on an external monitor, everything is still on the Mac. Make a backup first.

Can I keep using a MacBook with a flickering screen?

For a short time often yes, but a wearing cable can fail completely, especially if you move the lid a lot. Do not wait until the screen is fully black.

Is this covered by the warranty?

That depends on the model, its age and the cause. Look at what Apple or your seller offers first; see AppleCare or an independent repairer.

What if the external monitor shows nothing either?

Then the Mac's own graphics output is not working, or the Mac is not starting properly. Also look at a MacBook that will not start up.