Fujitsu AUXG18KVLA Service Manual page 78

Check point 4. Check serial signal (Reverse transfer signal)
Check serial signal (Reverse transfer signal)
• Check if indicated value swings between AC 90 V and AC 270 V at the outdoor unit terminal 1
—3.
• If it is abnormal, check the parts below.
– Outdoor unit fan motor in
• If outdoor fan motor is abnormal, replace outdoor unit fan motor and main PCB.
• If the checked parts are normal, replace the main PCB.
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).
2-1. E: 11. Serial communication error (Serial reverse transfer error) (Outdoor unit)
BLACK
1
WHITE 2
RED 3
BLACK L
N
WHITE
"Service parts information"
↓
End
↓
End
+
-
on page 03-57
- (03-6) -
2. Troubleshooting with error code