Mitsubishi Electric MSH-GE50VB-E1 Service Manual page 29

When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second.
Outdoor unit does not operate.
How to check mis-wiring
E
• Turn ON the power supply. (indoor/outdoor unit)
• Press EMERGENCY OPERATION switch once.
Yes
Correct them.
1. Turn OFF the power supply (indoor/outdoor unit) and disconnect indoor and outdoor
connecting wire on indoor side.
2. Short-circuit terminal block
3. Turn ON the power supply (indoor unit) and press EMERGENCY OPERATION switch once.
Is there 5 V DC between J205 + –J101 - on the deicer P.C. board?
Refer to outdoor unit service manual.
OBH529A
MUH-GE50VB
Start
After 3 minutes, mis-wiring is indicated
(0.5-second ON, 0.5-second OFF)
on OPERATION INDICATOR
lamp on indoor unit.
Is this mis-wiring, poor contact,
or wire disconnection?
No
- by lead wire.
N 3
Is there 20 V DC between both ends of
R132 on the indoor electronic control P.C.
board ?
( By tester, the stylus is between 0 ~ 20 V. )
Yes
• Turn OFF the power supply. (indoor unit)
• Connect indoor/outdoor connecting
wire.
Turn ON the power supply(outdoor unit).
Is there 230 V AC between outdoor terminal
block (TB1)?
Yes
Yes
Turn ON the power supply(indoor unit).
During EMERGENCY OPERATION,
is there 10 V DC between both ends
of R601?
(By tester, the stylus is between 5 ~10 V)
Yes
Replace the deicer P.C. board.
Short circuit of JPG and JPS on the indoor electronic control
P.C. board enables self -check to be displayed in 3 seconds.
No
Replace the indoor electronic
control P.C. board.
No
Check the outdoor power supply
and connection of wiring .
No
Replace the deicer P.C. board.
Make the wiring between CN730
No
on the deicer P.C. board and
outdoor terminal block correct.
29