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

LD351 13 times blink
EEPROM reading error
LD351 8 times blink
Communication error between micon
LD351 9 times blink
Indoor unit type mismatch error
LD352 1 time blink
LD351 Lit
OH thermistor abnormal
LD352 2 times blink
LD351 Lit
DEF(Hex) thermistor abnormal
Normal
Secure the connection of OH
thermistor connector
Please replace DEF thermistor.
Please replace OH thermistor.
Please replace Main PWB.
Please re-connect DEF thermistor.
Is OH thermistor connector connected properly?
LD301 also 13 times blink
Is DEF thermistor connector connected properly?
Is OH thermistor wire worn out or short circuit?
Normal
Is DEF thermistor wire worn out or short circuit?
Yes
Abnormal
Yes
Yes
Yes
Yes
No
No
No
No
No
Are CN21,CN22 connectors inserted properly?
Yes
Normal
Please check refrigerant cycle.
(Assuming refrigerant leak occurs)
No
Normal
Abnormal
Abnormal
Abnormal
Abnormal
Normal
If not recovered after check the
cycle, please replace the Main PWB.
(Thermistor detection circuit abnormal)
Secure the insertion of CN21,CN22 connectors.
Please exchange Main PWB.
(Microcomputer or EEPROM might be broken)
Please replace both Main PWB and Inverter PWB.
Wrong type (not multi type) of indoor unit is
connected with the outdoor unit. Look again carefully.
Please confirm the number of time of LD351 blinks?
Please replace Inverter PWB. If still NG after
(Microcomputer or EEPROM might be broken)
replace Inverter PWB, replace Main PWB.