Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 1086

FDC-HKXR
• When communication is checked by the connector CnI, each value will be as follows.
Connector
1 Common
2 12V power supply
3 Transmission from outdoor unit
CnI 4 Reception from outdoor unit
5 Watch dog (communication from inverter PCB to outdoor unit PCB)
6 Inverter overheat
7 Current cut
14
Error display:
Indoor unit
Red LED Stays OFF
Green LED Keeps flashing
Are automatic
address and manual address
coexstent on the same
network
NO
Defective outdoor unit
PCB → Replacement
(d) How to advance checks for each faulty symptom
(i) Inspection method when there is no error display
1) Four way valve does not switch during heating operation
Power supply
detected between outdoor
unit terminal 5 ~PCB
faston terminal 6
(black)?
NO
Defective outdoor unit
PCB → Replacement
1084
Contents of communication
[Automatic address setting and manual address
setting coexstents in the same network]
Outdoor unit
Red LED Stays OFF
Green LED Keeps flashing
YES
Repair to manual address
Defective 20 S →
YES
Replacement
V(analog tester)
0V
12V
Swings at 11~11.5V
Swings at 4.5~5V
Swings at 2~4V
5V: normal
0V: abnormal