Here are measures to troubleshoot a phone with a black screen:

1. Turn the phone off and on again.


2. Check if there is a removable battery. If there is, remove the battery and reinsert it.


3. Perform a soft reset to see if the phone responds normally.


4. If the phone still does not respond, a hard reset may be necessary.


5. Check if anything came loose inside the phone.


6. If the phone did not respond after trying these steps, then contact customer support.