McQuay MDS 150B - Page 85

Service Manual SM-MDS_(ii) 79
Master unit and slave unit communication error
Error Code: FE (For MC301), ER63 (For MDS-M PCB)
Check the connection of
the communication wire.
Is it connected correctly?
Reconnect and restart the system
YES
NO
Replace PCB
Turn off the unit
Is the communication
wire broken or loose?
YES
Replace the wire and restart the
system
NO
Is the DIP switch setting
on PCB correct?
NO
Reset the setting and restart the
system
YES
Swap the PCB between
Master and Slave unit. Is
the error follows the PCB?
YES
NO
6
Is the master and slave
unit PCB software version
same/compatible?
YES
NO
Replace the PCB / upgrade the
software version of the PCB