Symptoms
- Third-party charger doesn't charge the phone at all
- Charging is very slow with a third-party charger but fine with Apple's
- A warning about the accessory appears on screen
- Charger works with other devices but not the iPhone
Likely causes
- CommonCharger or cable isn't MFi-certifiedNon-certified accessories can fail Apple's authentication check and charge slowly or not at all.
- CommonCharger doesn't support the power delivery protocol iPhone expectsSome generic USB-C chargers don't negotiate voltage and current correctly with iPhone.
- PossibleDamaged or low-quality cable paired with the chargerEven a good charger can fail with a bad cable.
- PossibleCounterfeit accessoryCounterfeit chargers sometimes physically resemble certified ones but lack proper internals.
What to do
- Check the charger and cable for an MFi certification mark or documentation.
- Test the same iPhone with an official Apple charger and cable to confirm the phone itself charges fine.
- Try the third-party charger on another phone or device to see if it works at all.
- Look for any on-screen warning about the accessory when connecting.
- Replace just the cable first, since cables fail more often than the charger block itself.
- Avoid unusually cheap or unbranded chargers, especially for higher-wattage fast charging.
- If the charger works but very slowly, check its actual wattage rating against what iPhone needs for fast charging.
- Stick with certified accessories going forward if you find the phone works fine with Apple's own charger.
Tools and parts
MFi-certified charger and cableSearch: “MFi certified iPhone fast charger”
When to call a pro
This is an accessory compatibility issue, not something a repair shop needs to fix, unless the phone also fails to charge with Apple's own accessories.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.