Hitachi RAM-68NP3B, Service Manual, Page: 70 / 79

LD351 4 times blink
Switching failure
LD351 3 times blink
Abnormal low rotation
LD351 2 times blink
Peak current cut
LD351 14 times blink
DC voltage abnormal
LD351 12 times blink
Fan lock stop
Compressor start up fail. Un-insert compresor
connector and check the conductivity.
Abnormal
Abnormal
Operation stop when detect compressor
control abnormal. Can assume that heavy load
or driven circuit is abnormal.
Operation stop when detect abnormal current.
In this case, it can be assumed that the load
is too heavy or driven circuit is detected
abnormal.
Consider Q601,Q602 are broken.
Please replace the Inverter PWB.
(Q601,Q602 are abnormal)
Operation stop when abnormal outdoor fan
motor is detected. It can be assumed that
something blocking at fan blade area, fan
motor itself or driven circuit is abnormal.
Check if something block the
fan movement and confirm the
fan motor itself is not damage.
Remove the blocking object.
If the fan is abnormal, please
replace it.
Normal
Normal
Check fan motor connector.
Yes
Is F4 (2A fuse) blown?
Please secure connection.
OD fan motor
is normal
Please replace the Inverter PWB.
(Fan motor driven circuit is abnormal)
Please replace outdoor fan motor
and Inverter PWB. (Fan motor or fan
motor driven circuit is abnormal)
OD fan motor abnormal
Check OD fan motor. Detail on
how to check as mention in
label attached on top of
electrical cover.
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
Abnormal
Abnormal
Repair the abnormal portion.
Please replace compressor and
inspect again the Inverter PWB.
Normal
Is the compressor insulation
normal? Check with MegaOhm.
Based on [Self-check] diagnosis
result, replace the defect part.
Please conduct [Self-Check]
Check compressor wire
conductivity.
No
Please open the service valve.
Yes
Is service valve open?
Normal