Mitsubishi FDT100VNXWVH Service Manual page 164

Error code Indoor display
Remote control:
E48
Outdoor unit
Outdoor unit
inverter PCB
1. Applicable model
All models
2. Error detection method
Detected by rotation speed of
outdoor fan motor
3. Condition of error displayed
When actual rotation speed of
outdoor fan motor (FMo1, 2)
drops to 100min or lower
-1
for 30 seconds continuously,
the compressor and the
outdoor fan motor stop. After
3-minute delay, it starts again
automatically, but if this
anomaly occurs 5 times within
60 minutes after the initial
detection.
4. Presumable cause
• Defective outdoor unit control
PCB
• Foreign material at rotational
area of fan propeller
• Defective fan motor
• Dust on outdoor unit control
PCB
• Blow fuse
• External noise, surge
Note: When E48 error occurs, in almost cases F2 fuse (4A) on the outdoor unit control PCB is blown. There are a lot of cases that fuse is blown and
E48 occurs due to defective fan motor. And even though only the outdoor unit control PCB ( or fuse) is replaced,, another trouble (*1) could
occur. Therefore when fuse is blown, check whether the fan motor is OK or not.
After confirming the fan motor normal, check by power ON. (Don't power ON without confirming the fan motor normal.)
*1 The error which does not seem to relate E48 may occur like as "
communication error (E45) and etc.
RUN light
ON
Green LED
Keeps flashing
control PCB
Yellow LED
Keeps flashing
5. Troubleshooting
Does any foreign
material intervene in rotational area
of fan propeller?
fan rotate smoothly when turned
detected between (CNFAN Œ
(red)- (blue)) of fan motor
Power source reset
Is normal state restored?
TIMER light
Content
7-time flash
Outdoor fan motor anomaly
Red LED
1-time flash
Diagnosis
NO
Does the
by hand?
YES
Is DC280V
NO
connector?
Is F2 fuse blown?
YES
", Stay OFF of LED on outdoor unit control PCB, inverter
WAIT
163
- -
'20 • PAC-SM-351
Countermeasure
Remove foreign material.
YES
Replace fan motor.
NO
If resistance between ➀
(Vm):red - ➃ (GND):blue is
detected 1k Ω or lower, it is
faulty.
Check power source
NO
voltage.
Replace faulty fan motor
YES
and outdoor unit control
PCB.
Replace fan motor (If
NO
anomaly persists after
replacing fan motor, replace
outdoor unit control PCB.)
Malfunction by temporary
YES
noise