Rb Unit Transmission Pcb2 Parallel Communication Error; Rb Unit Controller Pcb Circuit; Rb Unit Communication Pcb - Fujitsu Airstage VR-II Series Service Manual

Trouble shooting 70
RB UNIT Error Method:
RB Unit transmission PCB2 parallel
communication Error
Detective Actuators:

RB Unit Controller PCB Circuit

RB Unit Communication PCB

Forecast of Cause : 1. Connection failure 2. Outside cause 3. Communication PCB failure 4. Controller PCB defectve
Check Point 1 : Reset Power Supply
Does Error LED indication show again?
Check Point 2 : Check RB Unit components
Check if RB Unit Communication PCB is removed.
Check Point 3 : Replace Communication PCB
Replace Communication PCB.
EJ1. 4 Indicate or Display:
Outdoor Unit : E. 1 4.1 / 1 4.2*
Indoor Unit : 1st: Operation LED 13 times Flash, Timer LED 1 Times
2nd:Operation LED 1 time Flash, Timer LED 4 Times Flash
Error Code : J 1 / 1 4
RB Unit : Power LED ON, Error LED Continuous Flash
* Outdoor unit indicates 1 4.1 or 1 4.2 (No communication from Indoor unit)
Service tool indicates Error 1 4.3 or J 1.1, when the service tool detects No
communication of outdoor unit or the communication Error of RB unit.
Detective details:
When Parallel Communication Error (Communication reset occurs continuously
more than specified times) is detected.
NO
04-79
Flash, Filter LED Continuous Flash.
Check Point 1-2 :
Check outside cause (Voltage drop or noise, etc.)
Instant drop ----- Check if there is a large load electric apparatus
in the same circuit.
Momentary power failure ----- Check if there is a defective
Noise ----- Check if there is any equipment causing harmonic
wave near electric line (Neon bulb or electric
equipment that may cause harmonic wave).
Check the complete insulation of grounding.
contact or leak current in the
power supply circuit.