Indoor Unit Fan Motor Check Procedure - Mitsubishi Heavy Industries SRK20ZSPR-S Technical Manual

blocks ② and ③ oscillating between
DC 0 and 20V?
YES
Indoor electrical components
are normal.
(b) Indoor unit fan motor check procedure
1) Indoor PCB output check
DC several V
(4-6 V)
CNU
⑥
⑥
2) Fan motor resistance check
Measuring point
① − ③
−
④ − ③
−
Replace indoor PCB.
(–)
GND
DC15V
⑤ ④ ③ ②
⑤ ④ ③ ②
FM
I
Resistance when normal
M
k
113
-
① ④
DC 308-336V
Indoor PCB
①
①
-
'17 • SRK-T-206
⑤
Measuring Voltage range when
point normal
① − ③ −
④ − ③
⑤ − ③
−