Hitachi RAM-90QH5, Service Manual, Page: 67 / 83

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INSPECTING OUTDOOR ELECTRICAL PARTS
LED number
Name Diagnosis
lamp 1
Diagnosis
lamp 2
Communications
lamp
Off Off Off
Off Off
Off Off
Off Off
Off
Off
Off
Case 1
Case 2 Blinks once
Blinks
Blinks On
On
On On On
On
On
On Normal operation
Thermistor abnormally
Abnormally stop
Normal off status or
unconnected
microcomputer power
source
Microcomputer reset
status (immediately
after inserting power
source or immediately
after power source
abnormally)
OVL1 operation
OVL2 operation
OVL3 operation
Normal operation
Normal operation
Normal operation
Normal operation
On
Case 3
Case 4
Case 5
Case 6
Case 7
Case 8
LD301 LD302 LD303 Status Checkpoints
If the LED is not on even when the
power source is connected the
microcomputer power source is
unconnected.
Inspection method 1
Abnormally stop is shown by the
number of times the LED blinks.
Inspection method 2
Thermistor abnormally is shown by
the number of times the LED blinks.
Inspection method 3
If is normal for LD301 to blink once
after the power source has been
inserted. If the unit stops when it is in
operation and LD301 blinks once, it is
possible that the power source has
been temporarily interrupted by
lightning or for some other reason.
Replace the control PCB if this occurs
frequently.
Check to see that the LED is either on or blinking.
Carry out inspections by examining the on/blinking status of LEDs 301-303.
Carry out inspections by examining the on/blinking status of LEDs 304-308.
LED NO.
Communication
Lamp
Communication
Lamp
Communication
Lamp
Communication
Lamp
Communication
Lamp
LD304 LD308 LD307 LD306 LD305 Status Checkpoint
Inspection methody 4
Name
Case 9 Off On On On On Communication
error
Check the connection of
indoor unit 1 (C1, D1)
Case 10 On Off On On On Communication
error
Check the connection of
indoor unit 2 (C2, D2)
Case 11 On On Off On On Communication
error
Check the connection of
indoor unit 3 (C3, D3)
Case 12 On On On Off On Communication
error
Check the connection of
indoor unit 4 (C4, D4)
Case 13 On On On On Off Communication
error
Check the connection of
indoor unit 5 (C5, D5)
➞