FRIEDRICH AIR CONDITIONING CO. 5-3
Troubleshooting
5-2-2 When the Touch Key pad and Led Display
1) Check points
(1) Is the voltage of the power source normal ? (the rating voltage ±10% range.)
(2) Is the electric wire in good contact ?(CN71, RY71)
(3) Is the connection of the assembly main PCB, and TOUCH KEY PAD in good
contact? (SW01-SW05)
Check the micom
(IC05) for a short,
and replace it.
Check the micom
(IC05) for a short,
and replace it.
Check the Q901~
Q905 for a short,
and replace it.
Check the micom
(IC05) for a short,
and replace it.
Normal operation
Check the micom
(IC05) for a short,
and replace it.
Replace the membrane key pad
Replace the membrane
key pad.
Y
N
Normal operation
N
N
N
N
N
N
Y
YY
YY
Y
Y
Turn off the power, and then turn it on again
five seconds later.
When the LED display is
not operated.
When the membrane key is
not operated.
Is the voltage of the micom
(IC05) No.1, 2, 38~43 port a
square wave?
Is the voltage of the
micom (IC05) No.13, 14 port
a square wave?
Is the voltage of the micom
(IC05) No.3, 4, 10, 11, 44 port
a square wave?
Is the voltage of the micom
(IC05) No.3, 4, 10, 11, 44
port a square wave?
Is the voltage of the
Q901 ~ Q905 square wave?
Check the IC06
for a short, and
replace it.
N
Is the voltage of the
IC06 No. 10~16 a square
value?
DB98_04511A(2)-2 2/18/03 4:12 PM Page 5-3