What sellers hide on used iPhones: mic, camera, charging port

Mistake: you assume a shiny screen means the phone is fine.

Myth: A working screen means everything else works

Fact: The screen can be fine while small parts fail. A phone can look perfect and still have a bad microphone, a shaky camera, or a loose charging port. Those parts wear out with drops, dirt, and time.

Myth: Cameras only fail from drops

Fact: Many camera problems come from scratches, dust, or software glitches. Tiny dust inside the lens will make images soft or show dark spots. That can be fixed sometimes, but not always. Front cameras can fail after water exposure, even if the phone seems dry.

Myth: If sound plays, the mic is fine

Fact: Playing music tests speakers, not the mic. The mic is small and can be blocked by lint, liquid, or a crushed cable connector. A working speaker does not mean the mic will pick up your voice clearly on calls or voice notes.

Myth: Charging port issues are obvious

Fact: A port can charge slowly, or only on certain angles, or only with some cables. Corrosion or bent pins can cause intermittent charging. Sellers sometimes hide this by charging the phone in store or by carrying a working cable that masks the issue.

Myth: A reset fixes everything

Fact: A factory reset can clear software problems, but it cannot fix broken parts or hidden water damage. Sells may factory reset before a sale to hide recent crashes or frozen apps. Hardware issues remain.

Myth: If the phone pairs with Bluetooth, it’s healthy

Fact: Bluetooth pairing checks wireless chips, not mics or cameras. You can pair to a speaker but still have a bad mic or a camera that freezes. Those are separate systems.

Fast check before you pay

• Make a call and ask the buyer to hold the phone like you will; test both ends of the call.

• Record a 30-second voice memo and play it back at normal volume.

• Take indoor and outdoor photos with both front and back cameras; zoom in on detail.

• Plug in your own cable and wiggle it gently to check for loose charging behavior.

• Inspect the port with a light for lint, corrosion, or bent pins.

• Check camera focus by tapping on a small object close up.

• Ask if the phone has ever been in water or had a screen replaced.

Mid-sale micro-moment: You hand the phone back and the seller plugs in their cable. Ask for the same cable you used. If charging stops when you remove your cable, that tells you the port is picky or damaged. A quick swap nails down intermittent charging.

How to test the mic quickly

Make a live call and then a voice memo. A call shows how the other person hears you. A voice memo shows how the phone records your voice locally. If the call is fine but the memo is muffled, the network may be masking the issue or a secondary mic is failing. Try speaking at normal and loud levels. If the mic distorts on loud sounds, the mic element may be worn.

How to test the camera reliably

Take two shots: one of a textured surface close up and one far away. Look for soft focus, lens flare, or odd dark spots. Switch between photo and video. Try portrait mode and normal mode. Test both lenses if the phone has more than one. If the image shakes or the camera app crashes, that points to hardware or a bad update.

How to test the charging port without tools

Use a plain, known-good cable. Plug and unplug while watching the charge icon and the lightning or USB indicator. Wiggle the cable gently. If charging drops or the icon blinks, the port is loose or dirty. Ask to see the phone charge from 0 to 80 percent if the seller agrees; slow charging or sudden drops show problems.

Red flags to watch for

Short calls from the seller, refusal to let you test with your cable, or a phone that only charges on a wireless mat are red flags. Repaired phones can be fine, but ask who replaced the part and if original parts are used. If the seller hesitates when you ask to record a memo or take photos, that is a sign to walk away.

When repair is worth it

Some fixes are cheap: lint removal, a new lightning connector, or a camera clean. Other fixes cost more, like replacing a logic board or dealing with water damage. Ask for an itemized repair quote before you buy. Compare that to the price difference from a fully working unit.

A clean reset and a quick port check can be the difference between "easy money" and "not worth it."

Today’s takeaway: Test mic with a voice memo, test cameras with close and far shots, and test charging with your own cable before you pay.