Malfunction Of Transmission Between Indoor Unit And Remote Controller - Daikin RZQ100B8V3B Service Manual

Error Codes: System Malfunctions
4.3 Malfunction of Transmission between Indoor Unit and Remote Controller (U5)
1
Error code
Error generation
Causes
3 3
Troubleshooting
4
5
Caution
3–98
U5
The error is generated when the microprocessor detects that the transmission between the indoor unit
and the remote controller is not normal over a certain amount of time.
The possible causes are:
Malfunctioning remote controller
Malfunctioning indoor PCB
Outside cause (noise...)
Connection of two master remote controllers (when using two remote controllers).
Control by 2 remote
controllers
NO
All
indoor unit
PCB microcomputer
normal monitors
flashing
YES
Using
multicore
transmission wiring
between indoor unit
and remote
controller
NO
Is "U5" displayed
constantly?
YES
Be sure to turn off power switch before connect or disconnect connector, or parts damage may be
occurred.
SS1 of both
YES
remote controllers is
set to MAIN.
Resets
normally when
NO
power supply is turned
off temporarily.
YES
YES
NO
Set one of the remote
controllers to SUB, turn off
YES
the power supply
temporarily, then restart
operation.
NO
Indoor unit PCB
replacement.
Malfunction could be
produced by noise. Check
the surrounding area and
restart operation.
Change to
double-core
independent cable.
Failure of remote
controller PCB or
replacement of defective
indoor unit PCB.
Problem could be caused
by external factor (noise
etc.) other than
malfunction.
Part 3 – Troubleshooting
ESIE05-03