Mitsubishi Electric CITY MULTI PUHY-P108 Service Handbook page 272

(3) System connected to the system controllers (MELANS)
Error Code
6607 No ACK abnormality
(Contin-
ued)
Error
Error dis- Detection
source ad-
play
dress
system M-NET re- No ac-
controller mote con- knowl-
(SC) troller (RC) edgement
MA remote (ACK) at IC
controller transmis-
(MA)) sion to SC
Error definition and error detection method
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 remote controller
indicates the controller which did not provide the response (ACK).
Cause
method
1. Error display on some displays on
M-NET remote controllers
(1) Faulty wiring of the transmission
line for M-NET remote controller
(2) Disconnection or contact failure
of the transmission connector for
M-NET remote controller
(3) M-NET remote controller failure
2. Error occurrence on all IC in the
system with one outdoor unit
(1) An error is found by the outdoor
unit.
Total capacity error (7100)
Capacity code error (7101)
Error in the number of connect-
ed units (7102)
Address setting error (7105)
(2) Disconnection or short circuit of
the transmission line for the out-
door unit on the terminal block
for centralized control line con-
nection (TB7)
(3) Turn off the power source of the
outdoor unit
(4) Malfunction of electrical system
for the outdoor unit
3. Error display on all displays on M-
NET remote controllers
(1) Same causes as (1) - (4) de-
scribed in 2.
(2) When the power supply unit for
transmission lines is used and
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) System controller (MELANS)
malfunction
- 263 -
[ IX Troubleshooting ]
Check method and remedy
Check (1) - (3) on the left.
1) Check the LED display for troubleshoot-
ing on the outdoor unit.
-> If an error is found, check the check
code definition, and correct the error.
-> If no error is found, check the cause
2)
2) Check (2) - (4) on the left.ÅB
Check (1) - (4) on the left