Fujitsu Airstage V-II Service Manual page 163

SERVICE PARTS INFORMATION 4
Main PCB
Filter PCB (Main)
PWB UNIT (CT)
Check Filter PCB (Main) -1
Is Fuse (15A/400V) open?
Is Fuse (3.15A/250V) open?
YES
Check Filter PCB (Main) -2
PCB pattern and parts on PCB defective?
NO
Check Filter PCB (Main) -3
(1) Replace blown fuse.
(2) Disconnect all the connection wires between
the Filter PCB (Main) - Main PCB.
(3) Is there a short between L1-N, L3-N, and
L1-L3?
NO
Check Main PCB -1
(4) Connect all the connection wires between the
Filter PCB (Main) - Main PCB disconnected
at step (2).
(5) The same as step (3), is there a short
between L1-N, L3-N, and L1-L3?
NO
Check CT PCB
(For AJ*A72L/90L, to next step)
(6) Disconnect the connection wires between the
CT PCB - Main PCB.
(7) Is there a short between pins 1-3 of the CT
PCB connector?
NO
Check Main PCB -2
(8) Disconnect the wires of the pressure sensors
(high pressure/low pressure) connected to
the connector of the Main PCB.
(9) Is there a short between pins 1-3 of the Main
PCB side connector?
NO
Check pressure sensors (high pressure/low pressure)
Refer to 6-6-6 Pressure sensor check.
Check Main PCB -3
(10) Disconnect the Main PCB side connector of
the connection wires (8-pin connector)
between the Main PCB - Inverter PCB.
(11) Is there a short between pins 1-2 of the Main
PCB side connector (8 pins)?
NO
Turn on the power.
(12) Reconnect all the connection wires disconnected up to (1)-(11) to their original places.
(13) Turn on the AC power.
If the LED of the Main PCB does not light or blink, replaces the Main PCB, Filter PCB (Main), CT PCB.
NO
YES
Replace Filter PCB (Main)
YES
Replace Filter PCB (Main)
YES
Replace Main PCB
YES
Replace CT PCB
YES
Replace Main PCB
YES
Replace Main PCB
04-101