This page shows Sony lamp location and bulb replacement. Sony DIY Bulb Guide
The XL2100 Lamp assembly is located behind the grill, under the front screen. Thumbscrews on left and right loosen and the panel pulls off.
Open Lamp access door by loosening the thumbscrew on the front. The lamp is behind the door and attached by two mounting screws. The mounting screws require an "Allen" or Hex key.
Never attempt to access the bulb or open the door when the bulb is hot. Allow 30 minutes to cool.
Look for specific LED indicator codes
on the front of the TV. An explanation of the most likely fault is in your Sony user's manual. Links to free Sony user manuals are also on the link above. Lots of instructions regarding safety, mercury disposal, removing the lamp.
Do not buy a bulb and waste your money if any Sony TV Optical Block or Optical Engine Faults
are or were visible before bulb failure. easyab