Wired Remote Controller Communication Error - Fujitsu AS G18KMTA Series Service Instruction

Trouble shooting 3
INDOOR UNIT Error Method:
Wired remote controller
communication error
Detective Actuators:
Indoor unit Controller PCB
Wired remote control
Forecast of Cause:
1. Terminal connection abnormal
Check Point 1 : Check the connection of terminal
After turning off the power, check & correct the followings.
Check the connection of terminal between remote control and Indoor unit,
and check if there is a disconnection of the cable.
OK OK
Check Point 2 : Check Remote control and Controller PCB
Check Voltage at CN300 (Terminal 1-2) of UTY-TWRXZ2 (Communication kit).
(Power supply to Remote control)
>> If it is DC12V, Remote control is failure. (Controller PCB is normal)
>> If it is DC 0V, Controller PCB is failure. (Check Remote control once again) >> Replace Controller PCB
Upon correcting the removed connector or mis-wiring, reset the power.
Indicate or Display:
Outdoor Unit : No indication
Indoor Unit : Operation lamp: 1 time Flash, Timer lamp: 2 times Flash
Economy lamp: Continuous flash.
ERROR CODE : [E : 12]
Detective details:
Upon receiving the signal more than 1 time from Wired Remote,
but the same signal has not been received more than 1 minute
(3 Wire type), 2.5 minute (2 Wire type)
2. Wired remote control failure
02-12
3. Controller PCB failure
>> Replace Remote control
DC