Hitachi RAC-50NH5, Service Manual

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3. Only indoor fan does not operate (other is normal)
Can the fan be stopped by
remote control?
Are pulse signals output at
microcomputer pin
15
-
18
when auto
swing is turned on in the fan mode?
Is a voltage over 15V or below 10V
being generated on the 12V line
Replace IC111
Replace the microcomputer
Check IC711. If it is normal,
replace the air deflector motor.
Replace the microcomputer.
Replace the indoor fan motor.
Replace the microcomputer.
Perform final operation check.
Perform final operation check.
The microcomputer fan PWM
output (pin) is “Hi”
Yes Yes
Yes
Yes
No
Yes
Yes
Yes
No
No
Yes
No
No
Set to the “Hi” fan mode.
The operation lamp lights once and goes out in 5-10 seconds.
Disconnect CN10 and set to the fan mode again.
Replace the indoor fan motor.
The operation lamps lights once and goes out in 5-10 seconds.
Check to see if shorting etc. has occurred
in the P.W.B pattern
Check to see if the indoor fan is touching
the chassis, etc. If it does repair
Can the indoor fan be lightly turned by hand?
(Switch of main power before check)
4. Air deflector does not move (others are normal)
5. All systems stop from several seconds to several minutes after operation is started (all indicators
are also off)