What to do first
- Power cycle and update software/firmware.
- Swap known-good cable/charger/accessory (if relevant).
- Check heat/airflow and remove cases/dust.
- Run built-in diagnostics if available.
- If risk is high or symptoms persist, use a technician.
Directional signals
- Likely part: screen · confidence low · risk high
- Likely part: charging port · confidence low · risk medium
Sample cases exist for this combination; treat as directional.