Checking The Main P.w.b (Power Circuit) - Hitachi RAF-50FX8 Service Manual

6. Checking the main P.W.B (power circuit)

Is 35V being output to pin
⑤ based on C114 cathode
0V?
Yes
Is DC5V being output?
Yes
※1 During the operation is being stopped, 12V line may change to 7V.
Check whether the connection cable is
disconnected or connected reversely.
Check the outdoor unit P.W.B. if it is ok.
Is ICP1 normal? Less than
No
1Ω is normal. Above 1Ω is
blown (open).
Yes
Is the thermal fuse on the
terminal board blown
(open)?
No
Replace Q111, IC111.
No
Perform final operation check.
– 184 –
Replace ICP1. Check whether
deflector motor shorted and
also check ICP1. If IC111,
No
Q111, C114 and ZD121 are
defective, ICP1 will be
opened again.
Replace the terminal board.
Make sure to insert the
Yes
connection cable until the
end.
Replace IC112. Check whether
5V line is shorted, if so ICP1 is
opened again.