Mitsubishi Heavy Industries SRK100VNXPZSX Technical Manual page 93

blocks ② and ③ oscillating between
DC 0 and 20V?
YES
Indoor electrical components
are normal.
b) Indoor unit fan motor check procedure
i) Indoor PCB output check
i)
ii)
iii)
DC several V
(4-6 V)
CNU
ii) Fan motor resistance check
Measuring point
① − ③
−
④ − ③
−
7) Inspection procedure for blown fuse on the indoor PCB
( )
Faulty part, other than
fan motor
Replace the faulty part and the
fuse. Test-run then the unit for
checking.
Replace the indoor PCB and the fan motor. Check then the operation.
Replace indoor PCB.
(–)
GND
DC15V
⑥ ⑤ ④ ③
⑥ ⑤ ④ ③
FM
I
Resistance when normal
M
k
Is the fuse blown on the indoor
PCB?
YES
YES
Is there any faulty part (fan motor, etc)?
YES (Fan motor is faulty.)
Is there any damage on the internal circuit
of fan motor?
Check the resistance value to judge.
Replace the fuse on the indoor PCB.
When the operation is checked
without connecting the fan motor
connector, does the fuse blow?
YES
DC 308-336V
Indoor PCB
② ①
② ①
Go to the inspection procedure for electric
NO
equipment of indoor unit
(See page 91.)
NO
Replace the fuse, and check the operation.
NO
Replace the fan motor, and check the operation.
92
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'17 • PAC-T-257
① ④ ⑤
Measuring Voltage range when
point normal
① − ③
④ − ③
⑤ − ③
-
-