Ehs Does Not Work; Ehs (Plantronics) Does Not Work - Panasonic KX-DT543-B Service Manual

8.10. EHS Does Not Work

8.10.1. EHS (Plantronics) Does Not Work

Mesure the EHSDET voltage at Pin 7 of IC150.
Is it 0V?
YES
Measure the EHSTX signal between Pin 3 and Pin
4
of JK302.
See the communication waveform.
Refer to the waveform (18).
YES
Measure the EHSRX signal Pin 8 of IC150.
See the communication waveform.
Refer to the waveform (19).
YES
Confirm the EHS communication.
Can you use the EHS?
YES
END
Check the soldering.
Resolder or replace parts as needed.
NO
Related parts: R181,IC171,R177,Q170,R175,
NO
Related parts: R185,IC173,R170,R171,R172
NO
Related parts: R182,Q172,R180,IC172,
NO
Related parts: IC150,JK302
Note: Additional reference : See Table-4
35
KX-DT543/KX-DT543-B/KX-DT546/KX-DT546-B
D171,D172,JK302,
and Jumper chip
D170,C170,C171,and Jumper chip
R176,Q171,R173,R174,
and Jumper chip