Mitsubishi Electric PU(H)Y-P250YGM-A, Service Handbook

Page: 141 / 215

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[
IX
Troubleshooting ]
(1) System with the main remote controller connected
Error Code Error definition and error detection method
6607 No ACK abnormality The error is detected when no acknowledgement (ACK signal) is received after the
transmission. (eg. When the data is transmitted six times in a row with 30 seconds
interval, the error is detected on the transmission side.)
Note: The address/attribute appeared on the display on the main remote controller
indicates the controller where an error occurs.
Error
source ad-
dress
Error dis-
play
Detection
method
Cause Check method and remedy
Outdoor
unit (OC) Main
remote
controller
(SC)
MA remote
controller
(MA) No ac-
knowl-
edgement
(ACK) at
IC trans-
mission to
OC (1) Contact failure of transmission
line of OC or IC
(2) Decrease of transmission line
voltage/signal by exceeding ac-
ceptable range of transmission
wiring .
Farthest:
200 m or less
(3) Erroneous sizing of transmission
line (Not within the range below).
Wire diameter:
1.25mm
2
or more
(4) Indoor unit main board failure
Turn off the power source of the outdoor
unit, and turn it on again.
If the error is accidental, it will run normally.
If not, check the causes (1) - (4).
Indoor
unit
(IC) Main
remote
controller
(SC)
MA remote
controller
(MA) No ac-
knowl-
edgement
(ACK) at
SC trans-
mission to
IC 1. Error occurrence on all IC in the
system with one outdoor unit
(1) Total capacity error (7100)
(2) Capacity code error (7101)
(3) Error in the number of connect-
ed units (7102)
(4) Address setting error (7105)
(5) Disconnection or short circuit of
the transmission line for the out-
door unit on the terminal block
for centralized control line con-
nection (TB7)
(6) Turn off the power source of the
outdoor unit
(7) Malfunction of electrical system
for the outdoor unit
1) Check the LED display for troubleshoot-
ing on the outdoor unit.
->If an error is found, check the error
code definition, and correct the error.
->If no error is found, check 2).
2) Check (5) - (7) on the left.
2. Error occurrence on all IC
(1) Same causes as (1) - (7) de-
scribed in 1.
(2) The male power supply connec-
tor is connected to the female
power supply switch connector
(CN40) for the transmission line-
for centralized control
(3) Disconnection or shutdown of
the power source of the power
supply unit for transmission line
(4) Main controller malfunction
Check voltage of the transmission line for
centralized control.
20V or more : Check (1) and (2) on the
left.
Less than 20V : Check (3) on the left.