Cracked glass, dead touch, a black display and most Face ID faults on an iPhone are fixed by the same part — the screen assembly — because the glass, digitiser and display panel are bonded together as one unit. Knowing which symptom you have still matters, mainly to rule out the battery or motherboard first, and to flag the one genuine exception where a screen alone might not be the full fix. Here's how to diagnose it properly before you order.
Match your symptom
| What you see | Likely cause | Screen fixes it? |
|---|---|---|
| Black screen, but phone still vibrates, rings or shows charging light | Failed display, board OK | Yes |
| Cracked glass, touch and display still work | Cosmetic — glass/digitiser will fail eventually | Yes, when ready |
| Touch unresponsive or erratic, no visible crack | Digitiser damage from impact | Yes |
| Lines, dark patches, or flickering | Damaged display panel | Yes |
| "Face ID unavailable" after a drop | Sometimes a screen/sensor connector issue, sometimes a deeper fault | Sometimes — see note below |
| Completely dead — no light, sound or vibration | Battery or logic board | No — check power first |
The Face ID row is the one exception we can't promise on symptoms alone: it can be caused by a dislodged sensor connector during a drop (often resolved by a correct screen replacement and careful reconnection) or by deeper TrueDepth camera module damage that a screen alone won't fix. If Face ID fails after a drop, it's worth getting a second opinion before assuming a screen replacement alone will resolve it.
Why this diagnosis is genuinely harder on iPhone than some Android phones
Direct answer: the TrueDepth camera system behind Face ID sits in the notch or Dynamic Island area at the top of the screen, physically close to the display assembly but not part of it — it's a separate module of its own. A hard drop can dislodge either the screen's own connectors or the TrueDepth module's connector, or both, and from the outside these look identical: "Face ID doesn't work after I dropped my phone." This is why we're upfront that we can't promise a screen replacement alone will always fix a Face ID fault, rather than making a blanket claim that would be wrong for some readers.
Ruling out the battery or motherboard first
Before ordering a screen, check for any sign of life: a charging light, vibration, or sound when called from another phone. If there's genuinely none of those, the fault is more likely the battery or motherboard, not the screen, and a new display won't resolve it. This single check takes under a minute and prevents the most common unnecessary purchase we see.
Why digitiser damage without visible cracking gets misdiagnosed
Of all the symptoms in the table above, unresponsive touch with no visible crack is the one most likely to be mistaken for something more serious — a software fault, a dying phone generally. There's nothing to see, so it doesn't intuitively read as a hardware problem. In reality, digitiser damage from an impact commonly occurs without any visible cracking on the glass surface, particularly when the impact is absorbed at an edge or corner rather than the centre of the screen. If your iPhone's touch has degraded or stopped following any drop, even a minor one, the screen assembly is the first and most likely place to look.
A closer look at the Face ID exception
Because this is the one symptom on this page where we can't give a simple yes/no answer, it's worth a more careful look at how to approach it in practice. First, confirm the phone wasn't already showing Face ID issues before the drop — a pre-existing software glitch is a different problem entirely from drop-related hardware damage. Second, check whether Face ID fails consistently or only sometimes; intermittent failure can point toward a partially-seated connector (more likely fixable by a careful screen replacement) rather than physical module damage (less likely). Third, if you're fitting the screen yourself, pay particular attention to the TrueDepth sensor cluster during removal — it's a genuinely delicate component, and rough handling during a screen swap can itself cause the very fault you're trying to fix. If Face ID still fails after a correctly fitted, tested new screen, the fault most likely sits in the TrueDepth module itself rather than the display, and that's a more specialist repair than we can supply a straightforward part for.
What getting this wrong costs you
iPhone screens generally aren't returnable once fitted, and a screen replacement won't change anything if the actual fault sits in the battery, logic board, or (for the Face ID case) the TrueDepth module specifically. Running through the checks above — confirming signs of life, matching your specific symptom, and treating a post-drop Face ID fault with appropriate caution — takes a few minutes and directly protects you from paying for a part that won't fix the problem.
Symptom clusters: what tends to occur together
Real-world faults often present as more than one symptom at once, which can be confusing when working from a single-symptom table. A hard drop commonly produces a cluster: visible cracking near the impact point, localised touch unresponsiveness near that same area, and occasionally a Face ID issue if the impact was near the top of the phone. Seeing multiple related symptoms together, all traceable to a single impact point, is actually a reassuring sign — it points toward a contained, single-event screen fault rather than something more systemic. Conversely, symptoms with no clear connection to any specific drop or impact (intermittent black screen with no trigger, touch faults that come and go without pattern) are more worth investigating further before assuming a screen fix will resolve them, since they can sometimes point toward a connector or board-level issue rather than the screen itself.
Testing thoroughly after a screen replacement
Whatever symptom brought you here, once you've fitted a new screen, test comprehensively before final sealing rather than a quick glance: check touch responsiveness in every corner of the display, not just the centre; check Face ID if applicable, ideally more than once; check the display for uniform brightness and colour with no residual lines or patches; and check that the original fault symptom is genuinely gone, not just less severe. This thoroughness matters more here than on a component swap for a less safety-relevant part, since re-opening a sealed iPhone is meaningfully harder than the first opening.
Once you've confirmed it's the screen
Find your model and current pricing:
- iPhone 16 screen guide — all models and screen types
- Full iPhone cost comparison — every model we stock
- Model identification guide — if you're not certain which iPhone you have
Ready to fit it yourself? See our step-by-step DIY fitting guide, including how to test Face ID before fully sealing the phone.
Delivery & returns
- Same working-day dispatch on orders placed before 4:00pm, Monday to Friday.
- 30-day returns if an item arrives faulty.
- UK-based customer service, 10:00am to 6:00pm.
Frequently asked questions
Can I just replace the glass without replacing the whole screen?
No — on iPhone the glass, digitiser and display panel are bonded as one assembly, so a cracked-glass repair means replacing the full screen unit.
My touch doesn't work but there's no crack — is it still the screen?
Yes, most likely. Digitiser damage from an impact doesn't always show as visible cracking.
Will Face ID definitely work again after a new screen?
Usually, if the fault was a dislodged connector, but not always — deeper TrueDepth sensor damage needs more than a screen swap. Test before fully sealing the phone.
How do I know if it's the screen and not the battery?
Check for any sign of life — a charging light, vibration, or sound when called from another phone. If there's genuinely none, the fault is more likely the battery or motherboard.
Why can't you promise a screen fixes Face ID every time?
Face ID depends on the TrueDepth camera module, a separate component near the screen. A drop can damage either the screen's connectors, the TrueDepth module, or both — and the symptom looks the same from the outside either way.
Is it safe to assume a cracked screen with working touch is low priority?
For now, yes, but not indefinitely — see our dedicated guide on repairing now versus waiting for how to judge the timing.
How can I tell if my Face ID fault is a connector issue or module damage?
Intermittent failure points more toward a partially-seated connector, which a careful screen replacement can resolve; consistent, total failure is more likely deeper module damage that a screen alone won't fix.
What should I be extra careful of when fitting a screen myself, regarding Face ID?
Handle the TrueDepth sensor cluster near the notch or Dynamic Island with particular care during removal — rough handling during the swap can itself cause a Face ID fault that wasn't there before.
Is it reassuring or worrying if I have several symptoms at once?
Often reassuring, if they're all traceable to one impact point — it suggests a contained, single-event screen fault. Symptoms with no clear connection to a specific drop are more worth investigating before assuming a screen fix will resolve them.
How thoroughly should I test after fitting a new screen?
Check touch in every corner, Face ID more than once if applicable, display uniformity, and that the original symptom is genuinely gone — before sealing, since reopening a sealed iPhone is harder than the first opening.