Rb Unit - No Power - Fujitsu Airstage VR-II Series Service Manual

Trouble shooting 75

RB Unit - No Power

Check Point 1 : Power supply
Is not the breaker down?
Instant drop ----- Check if there is a large load electric apparatus in the same circuit.
Momentary power failure ----- Check if there is a defective contact or leak current in the power supply circuit.
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.
OK
Check Point 2 : Fuse on the PCB
Is not open circuit ?
If the fuse was open state, check the cause of short circuit
on the AC circuit before replacing the spare parts.
NG (Short circuit on AC circuit)
Check Point 3 : Short circuit check on AC circuit
Disconnect AC Power input wires (W101,W102) and Check
short circuit
NG (Short circuit on AC circuit)
Replace Main PCB
Replace Main PCB
Forecast of Cause :
1. Power Supply failure 2. Outside cause 3. Electrical Component defective
NG (No Voltage DC 5.0V )
OK
Check Point 4 : Short circuit on SV coil
Short circuit between Pin No.1 and Pin No.2 of SV coil
Check
NG (Short circuit between Earth)
Replace SV Coil with Connector
Check Point 5-1 : Short circuit check on DC circuit
Check the DC (5.0V) on C1
NG (No voltage)
Check Point 5-2 : Short circuit check on DC circuit
Disconnect transmission PCB and check DC 5.0V on C1
04-84
OK
OK (DC 5.0V )
Replace Transmission PCB