Cause #1: A Dirty or Clogged Charging Port
This is the culprit in about 70% of the "won't charge" calls I get. Pocket lint, dust, and general grime pack into the Lightning port over time. It gets compressed every time you plug the cable it, and eventually it blocks the pins from making contact.
The fix is simple. You don't need compressed air or any fancy tools (though compressed air can work). The most reliable method I've used for years:
- Power off your iPhone. Don't skip this — you don't want to short anything.
- Take a wooden toothpick (not metal, not plastic — wood is soft enough not to damage pins).
- Gently scrape along the bottom edges of the port, moving side to side. You'll see lint come out.
- Blow lightly into the port or use a can of compressed air at an angle.
- Plug in and see if it charges.
You'd be amazed how much junk comes out of there. If you're using a case with a port cover, that helps, but if you don't, this is your first stop.
Cause #2: A Bad Cable or Adapter (And Yes, Third-Party Matters)
If the port is clean and it still won't charge, the next suspect is the cable. MFi-certified cables last longer, but even Apple's own cables fray at the connector. Look for blackened or bent pins, exposed wire, or a loose fit when plugged in.
Here's the thing I tell everyone: don't bother testing with a cheap gas station cable. Those often don't have the right resistance for the iPhone to recognize them. Borrow a friend's cable or use the one from your iPad if it's newer (they're cross-compatible).
Also check the adapter. A 5W charger from 2015 might not cut it if your iPhone is pulling 20W. But the real issue is usually the cable, not the brick. I've seen bent pins on the Lightning end way more often than dead wall adapters.
Quick test: plug the same cable into a Mac or PC's USB port. If it charges from the computer but not the wall, it's the adapter. If it doesn't charge anywhere, it's the cable or the port.
Cause #3: A Software or Firmware Glitch (Hard Reset Time)
Less common, but it happens. iOS can get stuck in a state where it ignores the charger. You might see the battery icon but it doesn't increase, or it shows "Charging" but stays at the same percentage.
Don't bother with settings toggles or resetting network settings — that's not the fix. What you want is a force restart. It's not a full wipe, just a RAM and power cycle.
- For iPhone 8 or later (including all Face ID models): Press and release Volume Up, then Volume Down, then hold the Side button until you see the Apple logo. Keep holding through the logo — let go after about 10 seconds.
- For iPhone 7/7 Plus: Hold the Volume Down + Side button together until the logo appears.
- For iPhone 6s and older: Hold Home + Side (top) button until the logo appears.
Once it boots back up, plug it in. If it starts charging, you're good. If not, it's likely a hardware issue — could be the charging IC or battery health.
Check your battery health in Settings > Battery > Battery Health. If it's below 80% and the phone is randomly shutting down, that's a worn battery, not a charging failure. But if the battery health is fine and it still won't charge after all this, you're looking at a trip to the repair shop.
Quick-Reference Summary
| Symptom | Likely Cause | Fix |
|---|---|---|
| No charge at all, plug feels loose | Dirty port | Clean with wood toothpick, power off first |
| Charges on computer but not wall | Bad adapter | Replace adapter |
| Charges sometimes, needs wiggling | Frayed cable | Replace cable (use MFi or Apple) |
| Shows charging but % stays the same | Software glitch | Force restart (hard reset) |
| Nothing helps, port clean, new cable | Hardware failure (battery/IC) | Battery replacement or service |
Don't skip the cleaning step. I can't tell you how many people bring me a phone that "just stopped charging" and it's five minutes of scraping lint out of the port. Start there, work through the rest, and you'll save yourself a repair bill.