HT-XT100 - Sony Audio Service Manual (repair manual). Page 5

ABOUT  PARTS  REPAIR  OF  EACH  BOARDS
When each boards installed in this unit are defective, individual 
electrical parts that the mount is done cannot be replaced. When 
each boards are defective, replace the mounted board or the whole 
parts including an applicable board.
Printed wiring board and schematic diagram that have been de-
scribed on this service manual are for reference.

NOTE  OF  REPLACING  THE  BT  NFC  BOARD  OR  THE  
NFC  MODULE
When replacing the BT NFC board or the NFC module, be sure to 
replace both at the same time.
The BT NFC board or the NFC module cannot replace with single.

WHAT  TO  DO  IF  PRTCT  IS  DISPLAYED
If the “PRTCT” (represents the “PROTECT”) is displayed on the 
screen display panel, AMP temperature protection circuit or USB 
charging current protection circuit is working.
In this case, there is a possibility that the MAIN board or the USB 
board is defective. Be sure to replace the MAIN board and the 
USB board at the same time.

If the system still does not operate 
properly, reset the system as follows:

While holding down the @/1 (on/
standby) button on the system, 
hold down the INPUT and 
VOL (volume) – buttons 
simultaneously for 5 seconds.
[RESET] appears on the display, and 
the settings of the menu and sound 
fields, etc. return to their initial 
status.