Android phone won't charge in the car

Symptoms

• Phone shows 'not charging' or charges very slowly through the car's USB port
• 12V car charger adapter doesn't power the phone at all
• Charging works when the car is running but not with it off
• Charging is inconsistent over bumps or vibration

Likely causes

• CommonCar's built-in USB port has low power outputMany factory USB ports are designed for data or slow charging only, not fast charging.
• CommonLoose or worn cable connection affected by vibrationRoad vibration can jostle a marginal connection loose repeatedly.
• Possible12V adapter charger is faulty or underpoweredCheap cigarette-lighter USB adapters can fail or deliver very little current.
• PossibleCar's accessory power cuts off when the engine is offSome vehicles only power USB ports and outlets while the ignition is on or in accessory mode.

What to do

1. Test the same cable and phone on a home wall charger to confirm the phone and cable both work normally.
2. Try a different USB port in the car if more than one is available.
3. Check whether the car's accessory power requires the ignition to be on or in accessory mode.
4. Try a different 12V-to-USB adapter if using one, since these commonly fail.
5. Secure the cable so it isn't pulled or stressed by vibration while driving.
6. Check your car's manual for the actual wattage of its USB ports, since older cars often only support 5W.
7. If the built-in port is simply low-power, use a dedicated 12V fast-charge adapter matched to your phone instead.
8. If charging still fails with a good adapter and cable in the car specifically, the car's port or wiring may be at fault.

Tools and parts

When to call a pro

If the car's own USB ports never charge properly even with good cables, a car electrician or dealer can check the vehicle's wiring or port.

Safety