Galaxy Z Fold5 Inner Screen Shows a White / Black Line (Then Goes Black): What’s Actually Happening

You open your Galaxy Z Fold5 like you’ve done a thousand times… and there it is:

• A razor‑thin white or black line along the fold
• Or a weird “bump” plus a bright line
• Or half the inner screen suddenly dead, while the cover screen is totally fine

You restart it, baby it, close it gently, open it again… and it’s either still there or getting worse.

Let’s talk about that specific problem:

Galaxy Z Fold5 inner screen: line along the fold → touch stops working → part or all of the inner display goes black, but the cover screen still works.

First things first: when to STOP right away

If you’re seeing any of this on your Fold5 inner screen:

• A thin vertical or horizontal white line near the crease
• A dark/black line down the center or across the hinge
• A tiny raised “ridge” or bump you can feel with your finger
• One half of the inner screen flickering, dim, tinted, or totally black
• Inner screen doesn’t wake when you unfold, but the cover screen is normal

Stop doing these things:

• Don’t keep opening/closing it “to see if it fixes itself.”
• Don’t press hard on the crease or try to “massage” the line away.
• Don’t peel or pick at the inner screen protector.
• Don’t heat it with a hairdryer or stick it in rice (yes, people try).

That line is rarely a software glitch. On this device, it’s a mechanical failure starting to show up on a very fragile OLED + ultra‑thin glass sandwich. Keeping it in use is how you turn a repairable situation into a “welp, that’s catastrophic now.”

If you’re already past the “thin line” stage and a chunk of the inner display is black or unresponsive, you’re firmly in do-not-keep-using-it territory.

Hit your Free Repair Quote button at this point. If your Fold is still important to your work / content / life, this is not a “see how it goes for a few months” kind of failure.

Why this happens (even when you “never dropped it”)

If you search around, you’ll see the exact same story over and over:

• Phone is 6–18 months old
• Owner swears there were no big drops
• A small bump or line appears at/near the crease
• Soon after, a bright white or black line shows up
• Then, half or all of the inner screen dies while the cover screen is fine

What’s actually going on under the hood is some combination of:

1. The hinge starting to fail and pushing into the panel

On some units, the hinge or associated parts wear or misalign just enough that:

• A tiny internal piece starts pressing into the ultra‑thin inner display from behind
• You see or feel a little “nub” or bump at the crease
• The pressure point cracks the OLED stack, which shows up as a line or dead strip on the screen

Once that line shows up, the damage is already done internally.

2. Micro‑fracture of the foldable OLED / UTG stack

The inner display is:

• A flexible OLED panel
• Sitting under ultra‑thin glass and film layers
• Bent hundreds of times at the same point

Even without a dramatic drop, small repetitive stresses + a slightly imperfect fold + temperature swings can eventually turn into a micro crack across the fold area. That crack often presents as:

• A perfectly straight white or black line
• Touch not working on one side
• A “curtain” effect where one half slowly fades or goes black

3. Dust or debris at the hinge / crease

All it takes is a grain of sand or a tiny bit of grit in the wrong place:

• It gets dragged across the inner display as you fold/unfold
• It creates a thin scratch or pressure point at the crease
• Over time, that turns into the dreaded line or a localized crack

You don’t need a dramatic “shattered” moment. It can just quietly hit a breaking point one day when you unfold it.

Why ignoring it makes things worse

Most Fold5 owners try to “live with it” for a while:

• “It’s just a line, the rest of the screen is fine.”
• “I can still use the cover screen, I’ll deal with it later.”

Here’s what usually happens if you keep using it in that state:

• The crack propagates further across the display with every fold
• More pixels die, the line thickens or spreads
• Touch stops working on larger areas of the inner screen
• Additional stress can damage the new panel and the hinge assembly underneath

By the time some people finally seek help, their Fold is:

• Inner screen dead
• Hinge not folding smoothly
• Sometimes showing signs of internal delamination or burn-in patterns around the damage

At that point you’re not just in “screen swap” territory — you may be in full inner assembly + hinge work land.

Why the “wrong” repair tech makes this a horror story

Foldables are not just big, bendy versions of normal phones.

A random kiosk or generalist shop can absolutely make this worse:

• Cheap “compatible” panels are often dimmer, have visible crease issues, or fail quickly.
• Mis‑aligning the fold or using the wrong adhesive stack can cause immediate re‑failure of the inner display.
• Sloppy handling can damage the thin backplate, frame, or tiny flex cables that run right along the hinge spine.

And because Fold5 inner screens are expensive parts, the “oops” factor gets very real – we’ve seen devices where:

• A bad screen swap killed the new panel in days
• The device came back with a looser hinge, dust ingress, or a worse crease
• Owners then had zero leverage with Samsung AND a non‑OEM mess inside

This is one of those repairs where you really don’t want three different techs learning on your phone.

What we actually do when a Fold5 comes in with this symptom

At Mad Lab Repair, when we see:

“Fold5, inner white/black line, cover screen OK”

we treat it as a structural failure, not just ‘screen broke.’ Our intake looks more like:

1. Microscopic inspection of the crease & hinge area
   • Looking for bumps, dents, subtle frame warping, dust scoring.
2. Inner panel + frame assessment
   • Deciding whether it’s just the inner OLED assembly or also frame/hinge-side components that need love.
3. Controlled disassembly
   • No rushing. Foldables punish impatience.
   • Proper heat, proper separation, proper handling of ultra‑thin flexes.
4. High‑grade replacement parts only
   • We’re matching the right inner assembly for your exact model and region, not some random “Z Fold screen” grab bag.
5. Rebuild, reseal, and sanity‑check the fold
   • We care about how it feels to open/close after the repair, not just what shows on the screen.

No cost ranges here on purpose — that’s how people get anchored and mad later. You send the phone, we evaluate the actual damage, and you get a clear quote before we touch anything.

When it’s time to bail out and get help

If you’re seeing any combo of these:

• White or black line along the Fold5 crease
• Inner screen randomly not waking when opened
• Section of the inner display dim, tinted, or totally black
• Inner touch dead on one side while cover screen is fine

You’re in the zone where:

• More folding = more damage
• Samsung may try to blame any tiny mark if you go warranty-only
• Random shops can easily turn this into a brick with expensive parts

At that point, your best move is simple:

Power it down, stop folding it, and get a proper diagnosis.

Hit your Free Repair Quote button, toss your Fold5 in a padded mailer, and let a lab that actually lives in this weird foldable world take over.

You bought one of the coolest phones on the market. A hairline line across the middle shouldn’t be the thing that retires it.

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