T
ro
ubl
eshooting
4-2
0
S
ams
u
ng
El
ectronics
4-3-8 Communication error after finishing tracking (E202)
1
.
Chec
k
items
1
)
I
s
the
comm
u
nication
ca
bl
e
short
/
open
?
2
)
I
s
there
a
response
from
the
indoor
u
nit
PCB
?
2
.
Chec
k
proced
u
re
No
Yes
Is there a response from the indoor unit PCB
?
No
Yes
In this case, is the
voltage waveform
b
etween the lines s
q
uare
wave with amplitude over ±0.7
V
as shown
in the following picture
?
+0.7
V
-0.7
V
Good
Bad
Chec
k
the communication ca
b
le and
e
x
change the indoor unit PCB
?
Remove the communication ca
b
le
connecting the outdoor unit to indoor unit,
and measure the signal on LINE
2
of the
outdoor unit with a scope
Reconnect the ca
b
le connecting
the outdoor unit to the indoor unit
and restart the unit.
If the communication still doesn’t wor
k
,
e
h
t
e
c
a
l
p
e
r
indoor unit PCB and
Chec
k
the communication
ca
b
le in each PCB
and replace the PCB
Yes
Is the power
/
communication
ca
b
le connected correctly
?
No
Connect the power
/
communication
ca
b
le correctly.
outdoor unit PCB in order of mention.
cf.) If there is no oscillo scope, it can
b
e replaced multimeter instead of osillo scope.