Fujitsu ASU18RLF Service Instructions Manual page 46

Trouble shooting 2
INDOOR UNIT Error Method:
Serial Communication Error
(Serial Forward Transfer Error)
Detective Actuators:
Indoor unit controller PCB
Forecast of Cause:
1. Connection failure
Test 1-1 : Reset the power and operate
Does error indication reappear?
YES
Test 2 : Check connection
Check any loose or removed connection line of
between indoor unit and outdoor unit.
>> If there is an abnormal condition, correct it by
referring to Installation Manual or Data &
Technical Manual.
Check connection condition in control unit.
(If there is loose connector, open cable or miss-wiring)
OK
Test 3 : Check the voltage of power supply
Check the voltage of power supply
>> Check if AC187V(AC208V-10%) - 253V(AC230V+10%) appears
at outdoor unit terminal L1 - L2.
OK
Test 4 : Check serial signal (Forward transfer signal)
Check Serial Signal (Forward Transfer Signal)
>> Check if Indicated value swings between AC30V and AC130V at Outdoor Unit Terminal 2 - 3.
>> If it is abnormal, replace Controller PCB.
>> If it is abnormal, Check Indoor unit fan motor. (SERVICE PARTS INFORMATION 5)
>> If Indoor unit fan motor is abnormal, replace Indoor unit fan motor and Controller PCB.
BLACK
1
2
WHITE
RED
3
Indicate of Display:
Indoor Unit
Operation lamp : 1 time Flash
Timer lamp
ERROR CODE : [E : 11]
Detective details:
When the outdoor unit cannot properly receive the serial signal from
indoor unit for 15 seconds or more.
2. External cause 3. Controller PCB failure
NO
Test 1-2 : Check external cause such as noise
+
-
02-06
Outdoor Unit
A
1 1
: 1 time Flash
1 1
: Light ON
Check if the ground connection is proper.
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).
Monitor
B C D E F
1
1
: Light OFF n : n time blinking