Samsung AVXC4H052/072/100/110/145CE, Service Manual

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Troubleshooting
4-58 Samsung Electronics
Outdoor unit display
4-3-19 Communication error between Indoor & Outdoor units after Completing Tracking
× (Operation) ◑ (Timer) ◑ (Fan) × (Filter) × (Defrost)
• Communication error between indoor/outdoor units and/or the erroneous setup switch setting for the
number of indoor units installed.
Indoor unit display
Criteria
Cause of problem
• When the communication between indoor/outdoor units cut-off for 2 minutes (all chambers fail to receive)
1. How to check
Yes
Press the reset key (K3) of the outdoor unit
PCB then check the display part.
At that time, is the power
between the 2 lines a square wave?
Is there any response from
indoor units on the display part
during tracking?
Remove a communication line from the
outdoor unit to indoor units then measure
2 lines on the outdoor unit with SCOPE.
Reconnect the communication line from the
outdoor unit to indoor units then remove all
communication connectors on the indoor unit PCB
then find an indoor unit that hampers communication
by making a connection to each unit and replace
indoor unit PCB after checking out lines.
After 2 minutes, find an indoor unit than
shows a communication error then check if PCB
address setup has overlapped. (If an indoor unit’s
address is overlapped, communication error occurs)
- In that case, all indoor units with wrong address setup
for more than 2 will have communication error.
Check the outdoor unit PCB
communication line and connector
then replace the PCB
0.7V
0.7V
Good
Defective
If there is any problem with the address, check the
communication line then replace indoor unit PCB.
Yes
No
No
Yes
* If communication error occurs, please refer to
pages 4-50 see essential pre-checkup details.