U5" Malfunction Of Transmission Between Remote Controller And Indoor Unit; Indoor Unit - Panasonic U-4..6ML5XPQ Service Manual

Troubleshooting by Indication on the Remote Controller
U5
3.45 " "
Malfunction of Transmission between Remote
Controller and Indoor Unit
U5
Remote
Controller
Display
Applicable AII indoor unit models
Models
Method of In case of controlling with 2-remote controller, check the system using microcomputer is signal
transmission between indoor unit and remote controller (main and sub) is normal.
Malfunction
Detection
Malfunction Normal transmission does not continue for specified period.
Decision
Conditions
Supposed
Causes
Troubleshooting
196
Malfunction of indoor unit remote controller transmission
Connection of two main remote controllers (when using 2 remote controllers)
Defect of indoor unit PC board
Defect of remote controller PC board
Malfunction of transmission caused by noise
Be sure to turn off power switch before connect or disconnect connector,
Caution or parts damage may be occurred.
Using
2-remote controllers
control.
NO
All indoor
PC board microcomputer
monitors blink.
YES
Multi-core
cableis used for the
indoor unit remote controller
transmission
wiring.
NO
SS1 of
YES
both remote controllers
is set to "MAIN."
NO
Operation
NO returns to normal when
the power is turned off
momentarily.
YES
YES
Urban Multi ML5 · Mini UM · Heat Pump
YES
Set one remote controller to
"SUB"; turn the power supply
off once and then back on.
NO
Replace indoor unit PC
board.
There is possibility of
malfunction caused by noise.
Check the surrounding area
and turn on again.
Switch to double-core
independent cable.
replacement
Defect of remote controller PC
board or indoor unit PC board.
Replace whichever is
defective.
Troubleshooting
(V2823)