Table 11-7-1
Diagnosis/Process flowchart Item
Preparation
Check
Check
Operation
Measure-
ment
Check
Stop
Check
Measure-
ment
Contents
Tu r n “OFF” the power supply
breaker, and remove 3P
connector which connects
inverter and compressor.
• Check whether 15A fuse
on the control board
assembly is blown or
not.(F01)
Turn on the power breaker,
and operate the air condi-
tioner in COOL mode by time
shortening.
Measure terminal voltage of
the electrolytic capacity.
After operation, turn off the
power breaker after 2
minutes 20 seconds passed,
and discharge the electro-
lytic capacitor by soldering
iron.
Check voltage between
motor phases.
• Is not winding between 
Q
-
R
‚ 
R
-
S
, or 
Q
-
S
 opened
or short-circuited?
• Is not frame grounded with
Q
, 
R
, or 
S
?
Summary
If fuse was blown, be sure to
check the electrolytic
capacitor and diode block.
(DB01)
• Connect discharge
resistance (approx. 100Ω,
40W) or soldering iron
(plug) between +, –
terminals of the electro-
lytic capacitor (760µF) of
C07 (with printed
WARNING ELECTRIC
SHOCK)
on P.C. board.
OK 
if 760µF → DC290 to 400V
Remove CN31 while pushing 
the part indicated by an 
by an arrow because CN31 is 
a connector with lock.
→ Resistance between
phases should be
approx. 16 to 51Ω
→ Should be 100MΩ or
more.
Replace 
outdoor 
fan motor.
Remove connector 
of compressor.
NG
NG
NG
NO
OK
OK
OK
YES
Check 15A fuse
(Part No.F01).
Does outdoor 
fan rotate?
Replace fuse.
Check 
electrolytic
capacitor, diode
block (DB01), 
etc.
Check 
electrolytic 
capacitor, diode 
 (DB01),
etc.
Remove connector 
CN31 of outdoor fan 
motor, and using a 
tester, check resistance 
value between every 
phases at motor side.
Check 
terminal voltage
of electrolytic 
capacitor.
BA
760
µ
F:450V 
Discharging position
(Discharging period
10 seconds or more)
Plug of 
soldering iron
11-7. How to Diagnose Trouble in Outdoor Unit
11-7-1. Summarized Inner Diagnosis of Inverter Assembly 
(RAS-05, 07, 10, 13)