Fujitsu AUXB04GALH Service Manual page 153

Trouble shooting 75
Error Contents :
Transmission Error
Condition :
Normal communication with Indoor unit has been suspended for longer than 1 minute.
Cause 1 : DIP switch setting defective
Check setting of DIP-SW1-4, 1-5, 1-6.
Cause 2 : External noise
Remove or shut out external noise source.
Symptom :
LED repeats flashing 0.5sec ON & 1.0sec OFF.
OK
Cause 3 : Ext. Switch Controller is defective.
Replace External Switch Controller.
OK
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