Troubleshooting · not a buying list

Why is my wireless charger so slow?

Check the whole power path before replacing the charger. The advertised peak, the adapter’s input power and the power reaching a phone are different quantities.

Check my phone, puck, case and adapter

1. Identify the exact phone and puck

A generation name or a “magnetic” label is not enough. Read the charger’s model code on its cable or underside. For example, Google’s support reference distinguishes the original Apple MagSafe puck from the 2024 version when used with Pixel 10 phones. Google’s cross-brand guidance.

2. Read the adapter’s output—not only its total wattage

Check one port’s available watts and the voltage/current profile. A large multiport total does not establish the budget of the particular port while other devices are connected. Apple lists a 15 V / 2 A profile for its faster MagSafe path; Samsung’s EP-P2900 specifies its own adapter/PPS requirement. Apple input profiles · Samsung EP-P2900 requirements.

Do not estimate the fallback with a percentage. A 20 W adapter attached to a 25 W wireless charger does not imply “20 W delivered to the phone.” A source-backed fallback rule or a properly characterized measurement is needed.

3. Check the exact case and remove obstructions

Confirm the case maker’s listing for the exact phone and charging system. A wallet, card or metal plate between the surfaces is not a harmless test variable. Remove obstructions. On models where the magnetic charging arrangement requires a suitable case, testing without it is not an equivalent alignment test. Apple handling guidance · Samsung case requirement.

4. Compare like-for-like conditions

Record the starting battery level, elapsed time, screen state, case, adapter, room conditions and software. Change one item, then repeat under comparable conditions. Do not compare a cool, screen-off test at a lower battery level with a hot navigation session near full charge. That comparison does not isolate a charger fault.

If equipment feels unsafe, stop using it and follow the manufacturer’s support guidance. Let it cool naturally; do not bypass thermal protections. Google includes cooling and firmware checks in its Pixelsnap troubleshooting. Google troubleshooting.

5. Record a useful observation, not an invented diagnosis

The private test log keeps your configuration and timed battery change together. A normalized percentage-point rate is useful for organizing observations, but it is not a watt measurement, full-charge prediction or proof that a particular component is defective.

A published maximum is conditional. A missing compatibility rule means “not established here,” not “will never work.” Escalate unexplained disconnects or unsafe behavior to the manufacturer instead of repeatedly forcing a test.

References reviewed 2026-10-02. Diagnostic workflow is our own; no independent hardware test results are claimed.