You're sitting there, maybe finishing a spreadsheet or scrolling through some old photos, and then you see it. A single, flickering flicker. Then, a thin, needle-sharp horizontal line cuts right across your dock. Or maybe it's at the top. Honestly, it’s soul-crushing because that MacBook Pro 2017 wasn't exactly cheap. You try restarting. You reset the NVRAM because some forum from 2019 said it works. Nothing.
The reality is that horizontal lines macbook pro 2017 issues are legendary in the Mac community, and not in a good way. This specific era of Apple design was obsessed with thinness, which led to some pretty questionable engineering choices. We’re talking about a time when the "butterfly keyboard" was a thing and the "Stage Light" effect (Flexgate) was just starting to make headlines. But the horizontal lines? That’s a slightly different beast, often tied to heat, voltage, and a very specific display controller failure.
What’s actually happening inside your screen?
It’s usually not a software glitch. If you take a screenshot and the lines don't show up when you view that image on another device, you’ve basically confirmed it’s hardware. Bummer. The 2017 model uses a specific T-CON (Timing Controller) board that sits right at the bottom of the display assembly. This board is responsible for telling every single pixel on that Retina display exactly what to do.
Heat is the primary villain here. Because the 2017 MacBook Pro vents its hot air directly toward the bottom of the screen—right where those delicate display cables and the T-CON board live—the components undergo constant thermal expansion and contraction. Over years of use, the microscopic solder joints start to fail. Or, even more common, the flexible ribbon cables (the ones that wrap around the hinge) develop tiny fractures. When these cables fail, the signal gets "noisy," and that noise manifests as those annoying horizontal lines.
Sometimes it’s a "ghosting" effect where the lines appear to be a frozen version of a window you closed five minutes ago. That’s often a sign of the LCD panel itself failing due to voltage irregularities. It’s a mess.
The "Flexgate" connection
You might’ve heard of Flexgate. Apple actually acknowledged this for the 2016 13-inch models, admitting that the display backlight cable was too short and would eventually snap from the simple act of opening and closing the laptop. While the horizontal lines macbook pro 2017 issue is technically different from the backlight failure, it stems from the same design philosophy. The data cables are just as fragile as the backlight cables. If you’re seeing lines that change or disappear when you move the lid to a specific angle, you are looking at a physical cable tear.
Why the 2017 model is a special case
The 2017 refresh was supposed to fix the sins of 2016, but it mostly just refined them. It still used the same fundamental display architecture. Interestingly, users on the MacRumors forums and Apple Support communities have noted that the 15-inch models often suffer more from the "intermittent lines" issue because they have dedicated GPUs that pump out way more heat than the 13-inch integrated graphics.
It’s frustrating because Apple never launched a specific "Quality Program" for the 2017 horizontal line issue like they did for the 2016 backlight. You’re often left in a weird limbo. If you go to the Genius Bar, they’ll likely quote you $500 to $800 for a full display assembly replacement. They don't repair the cables. They don't swap the T-CON. They just rip the whole top half off and put a new one on.
Can you actually fix it yourself?
Short answer: Probably not. Long answer: It depends on how much you like staring at microscopic components and using a heat gun.
Since the display is a laminated unit, you can't just "pop it open" to see what's wrong. The LCD, the glass, and the backlight are all fused together. If the issue is the T-CON board or the ribbon cables, they are permanently attached to the display. Repair shops like Rossmann Repair Group have demonstrated that while you can technically bridge some of these connections, it is a nightmare of a job that requires a microscope and steady hands.
- The External Monitor Test: This is your first step. Plug your Mac into a TV or a monitor. If the lines aren't there, your GPU is fine. This confirms the problem is definitely the laptop screen itself.
- The "Cool Down" Method: If the lines only appear after an hour of work, your Mac is overheating. Try using an app like Macs Fan Control to crank the fans up early. Keeping the T-CON board cool can sometimes "hide" the symptoms for a few more months.
- Pressure check: Gently—and I mean gently—press on the plastic bezel at the bottom of the screen (where it says MacBook Pro). If the lines flicker or change, it’s a loose connection or a failing cable.
Dealing with the "Intermittent" Nightmare
The worst part about the horizontal lines macbook pro 2017 problem is that it’s rarely consistent. It’ll be fine for three days, and then suddenly, while you’re in a Zoom call, the bottom half of your screen looks like a barcode. This is usually due to the "gate drivers" on the side of the LCD panel. When the screen gets warm, the material expands, and a connection that was mostly okay becomes not okay.
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Some users have found temporary relief by "massaging" the edges of the screen, but honestly, that’s a gamble. You're just as likely to crack the LCD and turn a few lines into a total blackout.
Real-world repair costs and expectations
If you are out of warranty—which, let's be real, almost everyone with a 2017 model is by now—you have three main paths:
The Apple Way: $500-$800. You get a brand-new display and a 90-day warranty. It’s expensive, but it’s the only way to guarantee the problem goes away completely. Is a 2017 Mac worth an $800 repair in 2026? Probably not, considering you could buy a used M1 or M2 MacBook Air for that price which would absolutely destroy the 2017 in performance.
The Independent Shop: $300-$500. A good third-party shop might use a "Grade A" pulled screen from a donor Mac. It’s cheaper, but you’re still putting an old part onto an old machine. You might end up with the same problem a year later because the donor part has the same design flaws.
The DIY Replacement: $200-$350. You can buy the display assembly on sites like iFixit or eBay. Replacing the entire top assembly is actually one of the "easier" repairs on this model, but you still have to deal with those tiny pentalobe screws and very fragile connectors. One wrong move and you’ve shorted the logic board.
Is it time to give up on the 2017 MacBook Pro?
It's a tough pill to swallow. The 2017 Pro was a beautiful machine. But with the transition to Apple Silicon (M1, M2, M3), these Intel-based Macs are becoming "vintage" in Apple's eyes. MacOS updates are dropping support for older Intel chips, and the thermal issues that cause these horizontal lines aren't going away.
If you’re seeing these lines, you're on borrowed time. It might stay as one line for a year, or the whole screen might go pink tomorrow. It’s the unpredictability that kills you.
Actionable Next Steps
- Back up your data immediately. If the screen fails entirely, you’ll need to use an external monitor just to see what you’re doing. Make sure Time Machine is running.
- Check your serial number. Go to the Apple Support website and check if your specific unit falls under any "Service Programs." It’s a long shot for the 2017 lines, but sometimes they expand these programs quietly.
- Download Macs Fan Control. Set a custom fan curve so the fans kick in at 50°C instead of waiting for the laptop to get scorching hot. This might slow down the degradation of the screen cables.
- Lower your brightness. High brightness equals more heat at the T-CON level. Keeping it at 50-60% might give you a few extra months of usability.
- Evaluate the trade-in value. Even with a broken screen, some places will give you a bit of credit. It might be better to get $150 now toward a new Mac than to have a $0 paperweight next month.
The horizontal lines on a MacBook Pro 2017 aren't just a glitch; they are a symptom of a hardware design pushed to its absolute physical limits. Treat the machine with care, keep it cool, and start saving for its successor.