Toshiba MMU-P0121H Service Manual page 62

<For 4-way Air Discharge Cassette type>
Check code
[11]
Indoor fan motor alarm
Is there no connection error or
disconnection of connector CN33 and CN34 at
indoor motor P.C. board (MCC-1382) side?
Do resistance values between each
phases match at motor side when removing
fan motor connector CN33 at indoor motor
P.C. board (MCC-1382) side? (
When removing connector CN34 which is
provided to detect position of indoor fan motor
at indoor motor P.C. board (MCC-1382) side,
is resistance value between
at P.C. board side? (*2)
Is output of indoor fan motor position
detect signal of the removed connector
CN34 correct at P.C. board side ? (*3)
Is there no connection error or disconnection
on lead wire between indoor main P.C. board
(MCC-1361) connector CN28 and indoor motor
P.C.board (MCC-1382) connector CN27?
( * 1) Resistance value check between motors
• Aren't windings open/short between
• Doesn't ground failure occur between cabinet and
( * 2) Check of position detect resistance value of indoor fan motor
• Isn't the resistance between
( * 3) Fan motor position detect signal check
• Using a tester,measure voltage between
When turning the fan slowly with hands,voltage between each pins should swing from 0V to 5V.
… „
• Between and
NO
1)
*
YES
and correct
NO
OK
NO
 ‚
and ,
 „ opened or shorted? → Resistance value should be between 5kΩ to 20kΩ.
and

and
: 5V
Operation cause
1. Fan motor circuit connection error
2. Fan motor error
3. Indoor main P.C. board (MCC-1361) failure
4. Indoor motor P.C. board (MCC-1382) failure
YES
NO
NO
NO
YES
Check indoor main P.C. board (MCC-1361)
or indoor motor P.C. board (MCC-1382).
Failure Replace
‚ ƒ  ƒ
→ Resistance should be approx. 75Ω to 95Ω.
and , and
 ‚ ƒ
, , 10MΩ or more should be applied.
… →
3-59
Modify connection of connector.
Replace fan motor.
Replace fan motor.
Replace fan motor.
Modify connection of connector.