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

KX-DT543/KX-DT543-B/KX-DT546/KX-DT546-B

8.10.2. EHS (Jabra) Does Not Work

Mesure the EHSDET voltage at Pin 7 of IC150.
Is it 0V?
YES
Measure the JABRA_UTX signal between Pin 1
and
Pin 4 of JK302.
See the communication waveform.
Refer to the waveform (20).
YES
Measure the JABRA_URX signal at Pin 10 of
CN160.
See the communication waveform.
Refer to the waveform (21).
YES
Measure the JABRA_URX signal at Pin 10 of IC410
on Main PCB.
See the communication waveform.
Refer to the waveform (21).
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: [Main PCB] R453,R433,IC410
Flat Cable (Between Main PCB and Ope PCB)
Related parts: R183,R182,Q172,R180,IC172,
NO
NO
Related parts: [Main PCB] R454,CN400
Flat Cable (between Main PCB and Ope PCB)
NO
Related parts: IC150,JK302
Note: Additional reference : See Table-4
36
D171,D172,JK302,
and Jumper chip
[Ope PCB] R184,Q173,Q174,
R202,R203,R178,IC170,JK302,
CN160 and Jumper chip
R176,Q171,R170,R171,R172,
R173,R174,C170,C171,D170,
and Jumper chip
[Ope PCB] CN160, and Jumper chip