Fujitsu AOUH18LMAS1, Service Manual

Page: 58 / 215

Check point 4. Check serial signal (reverse transfer signal)
Check serial signal (Forward transfer signal)
RED
WHITE
BLACK
BLACK
WHITE
GREEN
+
-
N
L
3
2
1
• Check if indicated value swings between AC 30 V and AC 130 V at outdoor unit terminal 2—3.
• If it is abnormal, replace main PCB.
• If it is abnormal, check indoor unit fan motor. (Indoor unit fan motor in "Service parts informa-
tion" on page 03-80)
• If indoor unit fan motor is abnormal, replace indoor unit fan motor and main PCB.
End
Check point 1-2. Check external cause such as noise
• Check the complete insulation of the grounding.
• Check if there is any equipment that causes harmonic wave near the power cable (Neon light
bulb or any electronic equipment which causes harmonic wave).
End
2-2. E: 11.↓. Serial communication error (Serial forward transfer error) (Indoor unit)
- (03-16) -
2. Troubleshooting with error code
TR
O
U
B
LESH
O
O
TI
N
G
TR
O
U
B
LESH
O
O
TI
N
G