Mitsubishi Electric Mr.Slim PCY-P18KA.TH, Service Manual, Page: 23 / 38

Abnormal point and detection method
Cause
Countermeasure Check code
23
E0
or
E4
Remote controller transmission
error(E0)/signal receiving error(E4)
1
Abnormal if main or sub remote con -
troller cannot receive any transmission
normally from indoor unit of refrigerant
address “0” for 3 minutes.
(Check code : E0)
2
Abnormal if sub remote controller could
not receive any signal for 2 minutes.
(Check code: E0)
1
Abnormal if indoor controller board can
not receive any data normally from
remote controller board or from other
indoor controller board for 3 minutes.
(Check code: E4)
2
Indoor controller board cannot receive
any signal from remote controller for 2
minutes. (Check code: E4)
1
Check disconnection or looseness of indoor
unit or transmission wire of remote controller.
2
Set one of the remote controllers “main” if
there is no problem with the action above.
3
Check wiring of remote controller.
• Total wiring length: max. 500m
(Do not use cable × 3 or more.)
• The number of connecting indoor units:
max. 16 units
• The number of connecting remote control -
ler: max. 2 units
When it is not the above-mentioned problem of
1
–
3
4
Diagnose remote controllers.
a) When “RC OK” is displayed,
Remote controllers have no problem.
Turn the power off, and on again to check.
If abnormality generates again, replace
indoor controller board.
b) When “RC NG” is displayed,
Replace remote controller.
c) When “RC E3” or “ERC 00-66” is dis -
played, noise may be causing abnormality.
(If the unit is not normal after replacing
indoor controller board in group control,
indoor controller board of address “0” may
be abnormal.)
E3
or
E5
Remote controller transmission
error(E3)/signal receiving error(E5)
1
Abnormal if remote controller could not
find blank of transmission path for 6 sec -
onds and could not transmit.
(Check code: E3)
2
Remote controller receives transmitted
data at the same time and compares the
received and transmitted data. Abnormal
if these data are judged to be different
30 continuous times. (Check code: E3)
1
Abnormal if indoor controller board could
not find blank of transmission path.
(Check code: E5)
2
Indoor controller board receives trans -
mitted data at the same time and com -
pares the received and transmitted data.
Abnormal if these data are judged to be
different 30 continuous times. (Check
code: E5)
1
Set a remote controller to main, and the
other to sub.
2
Remote controller is connected with only one
indoor unit.
3
The address changes to a separate setting.
4
–
6
Diagnose remote controller.
a) When “RC OK” is displayed, remote con -
trollers have no problem.
Turn the power off, and on again to
check.
When becoming abnormal again, replace
indoor controller board.
b) When “RC NG” is displayed, replace
remote controller.
c) When “RC E3” or “ERC 00-66” is dis -
played, noise may be causing abnormal -
ity.
1
Contact failure at transmission
wire of remote controller
2
All remote controllers are set
as “sub” remote controller.
3
Miswiring of remote controller
4
Defective transmitting receiving
circuit of remote controller
5
Defective transmitting receiving
circuit of indoor controller board
of refrigerant addresses “0”.
6
Noise has entered into the
transmission wire of remote
controller.
1
2 remote controllers are set as
“main.”
(In case of 2 remote controllers)
2
Remote controller is connected
with 2 indoor units or more.
3
Repetition of refrigerant
address
4
Defective transmitting receiving
circuit of remote controller
5
Defective transmitting receiving
circuit of indoor controller board
6
Noise has entered into transmis -
sion wire of remote controller.
E6
1
Contact failure, short circuit or,
miswiring (converse wiring) of
indoor/outdoor unit connecting
wire
2
Defective transmitting receiving
circuit of indoor controller board
3
Defective transmitting receiving
circuit of indoor controller board
4
Noise has entered into indoor/
outdoor unit connecting wire.
Check LED display on the outdoor control cicuit
board.
Refer to outdoor unit service manual.
1
Check disconnection or looseness of indoor/
outdoor unit connecting wire of indoor unit or
outdoor unit.
Check all the units in case of twin triple
indoor unit system.
2
–
4
Turn the power off, and on again to
check. If abnormality generates again,
replace indoor controller board or outdoor
controller circuit board.
Note:
Other indoor controller board may have defect
in case of twin triple indoor unit system.
Indoor/outdoor unit communication
error (Signal receiving error)
1
Abnormal if indoor controller board can -
not receive any signal normally for 6
minutes after turning the power on.
2
Abnormal if indoor controller board can -
not receive any signal normally for 3
minutes.
3
Consider the unit abnormal under the
following condition: When 2 or more
indoor units are connected to an out -
door unit, indoor controller board can -
not receive a signal for 3 minutes from
outdoor controller circuit board, a signal
which allows outdoor controller circuit
board to transmit signals.
OCH550A