XSP-N1BT - Sony Car Audio Service Manual (repair manual). Page 12

5.  The Factor that One Touch Connection is Impossible 
The four following factors are considered as the factor that one touch connection is impossible. 
Guess and check the defective factor by each checking result.

Note: The four following factors are examples.

1 BT module defect

NG

―

NG

NG

2

Cover button SV 
assy defect

OK

NG

OK

NG

3

NFC tag data 
writing failure

OK

NG

OK

NG

4 Smartphone

OK

OK

OK

NG

Check the version of the NFC tag data writing application 
(NFCtagWriter application) for the servicing according to the 
procedure below.

Procedure:
1.  Start the NFCtagWriter application on the smartphone.
2.  Tap the “ 

 ” (menu button) or “   ” of the screen of the smart-

phone, then tap the “About” that is displayed on the screen of 
the smartphone.

3.  Check that version of the NFC tag data writing application for 

the servicing is displayed on the screen of the smartphone.