Daikin GYEQ20AN Service Manual page 178

Flow Charts for Troubleshooting
43
Outdoor/Indoor Unit Transmission Failure
Sub-code 0: The outdoor and indoor units are unable to communicate with each other within 50 seconds after
Description
of the failure
DIP switches misconfigured; indoor unit power supply not turned ON; fuse failure;
Possible
causes communication line connection failure; communication line incorrectly installed
of the failure
Flow chart
Power Supply System
NO
Are Outdoor Units
Powered ON?
YES
Does Earth Leakage
NO
Breaker (ELB) In Outdoor
Unit Remain Inactive?
YES
Are Fuses On Outdoor
NO
Unit Circuit Boards
Non-Defective?
YES
Is the indoor unit and NO
BS unit power turned on
YES
Check fuses on
circuit board.
167
power-ON or unable to communicate with each other within 3 minutes after they are connected
over the communication link (which means that all the indoor units have a transmission failure).
Check And
Turn ON
Power Supply.
Check And
Are You Sure Terminals
Repair
Earth Leakage.
Check
Starter System.
Communication Signal
Check Fuses.
Check And
Turn ON
Power Supply.
Communication System
Are the outdoor unit-indoor
NO
unit, and indoor unit-BS unit
Communication
communications cables
disconnected?
YES
NO
On Terminal Block Are
Not Loosened?
YES
Are You Sure
NO
Waveform Is Not
Distorted?
YES
Check whether
Transmission
Usage is not too
much.
Error
code
Check
Cables.
Retighten
Terminals.
Correct Wiring.
025911-01EN01
SiAUY361411EA
U4
Troubleshooting