Mitsubishi Electric PURY-P200 Service Handbook page 156

(2) In the case of the M-NET remote controller
Phenomena
Even if the operation SW on
1
the remote controller is
pressed, the display remains
unlit and the unit does not
start running.
(Power indicator
appear on the screen.)
2
When turning on the remote
controller operation SW, a
temporary operation display is
indicated, and the display
lights out immediately.
Check method & Handling
Check indoor LED3
Lighting?
Lighting
Extinguishing or
unable to confirm
Check for the change of LED
display by operating dip switch
SW1 for self-diagnosis.
*1 Check the transformer in accordance with the "TROUBLESHOOTING" in the indoor unit's service handbook.
Factors
(1) The power for the M-NET
transmission line is not supplied
from the outdoor unit.
(2) Short circuit of the transmission line
(3) Incorrect wiring of the M-NET
transmission line on the outdoor
does not unit side.
1 Disconnected wire for the MA
remote controller and
disconnected line to the terminal
block.
2 The indoor transmission line is
connected incorrectly to terminal
block (TB7) to the transmission
line for centralized control.
(4) Disconnected transmission line on
the remote controller side
(5) Remote controller failure
(1) The power for the indoor unit is not on.
1 The main power of the indoor unit (AC220~240V) is OFF.
2 The connector on the indoor unit controller board has come off.
3 The fuse on the indoor unit controller board has melted.
4 Transformer failure and disconnected wire of the indoor unit.
5 The indoor controller board failure.
(2) The main board of the indoor and the outdoor unit failure
As the indoor unit does not interact with the outdoor unit, the outdoor unit
model cannot be recognized.
Check indoor unit
power source
terminal block voltage
AC 220V?
Check fuse on circuit
Blown?
Check connection of
connector
Disconnected
Check transformer
resistance value
Within rated?
Check self-diagnosis
function of outdoor unit
Changed?
Faulty indoor
controller board
- 153 -
(a) Check voltage of the M-NET remote
NO
Check main power source
of power source wiring
YES
board
Check 220V circuit
YES
for short circuit
and ground fault
NO
YES
Improper connector
connection
NO
*1
Check cause of trans-
former disconnection.
NO
•Ground fault on circuit
board
YES
•Ground fault on sensor,
LEV
NO
Check self-diagnosis function af-
ter powering outdoor unit again
Changed?
YES
Accidental
trouble
YES
Checke method & Handling
controller transmission terminal.
i) If the voltage is 17V-30V
→ The M-NET remote controller is
defective.
ii) If there is 17V or less
→ Refer to 9.[4].8.(2) "Outdoor
unit transmission power source
circuit failure judgment".
When the factor (2) and (3)
apply, self-diagnosis LED of the
outdoor unit works and the
check code 7102 will be
displayed.
Apply power
source again
NO
Faulty outdoor
unit control
circuit board
Repair faulty
point