Mitsubishi Heavy Industries FDT71VNXVD Service Manual page 83

Error code
Remote controller: E48
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)
drops to 100min or lower
-1
for 30 minutes continuously,
the compressor and the
outdoor fan motor stop. After
3-minutes delay, it starts
again automatically, but if this
anomaly occurs 5 times within
60 minutes after the initial
detection.
4. Presumable cause
• Defective outdoor control
PCB
• Foreign material at rotational
area of fan propeller
• Defective fan motor
• Dust on outdoor control PCB
• Blow fuse
• External noise, surge
Note: When E48 error occurs, in almost cases F2 fuse (4A) [Model 71:F3 fuse (2A)]on the outdoor 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 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.
LED Green Red
Content
Indoor Keeps flashing Stays OFF
Outdoor Keeps flashing 1 time flash
5. Troubleshooting
Diagnosis
Does any foreign
material intervene in rotational area
of fan propeller?
NO
Does the
fan rotate smoothly when turned
by hand?
YES
Is DC280V
detected between (CNFAN
(red)- (blue)) of fan motor
connector?
YES
Power supply reset
Is normal state restored?
WAIT
93
– –
83
Outdoor fan motor anomaly
Remove foreign material.
YES
Replace fan motor.
NO
If resistance between
(Vm):red - (GND):blue is
detected 1k Ω or lower, it is
faulty.
NO
(1)
Check power supply
Is F2 fuse blown? NO
voltage.
Replace faulty fan motor
YES
and control PCB.
Note (1) Fuse of model 71 is F3.
Replace fan motor (If
NO
anomaly persists after
replacing fan motor, replace
control PCB.)
Malfunction by temporary
YES
noise
", Stay OFF of LED on outdoor control PCB, inverter
'10 • PAC-SM-137A
Countermeasure