Orion LCD2028D User manual

]=
ORION
SERVICE MANUAL
LCD2028D

1．Complete Unit Circuit diagram
POWER
SWITCH
LCD P
A
NEL
C ON 1
POWER BOARD
18V
C ON 2
18V
18V
REMOTE BOARD
CN2
CN4
VIDEO
CN22
A
UDIO
CN11
SPEAKER
C N3
ON / OFF ADJ
KE
Y
BOARD
MAIN BOARD
DVD
_
IR
CN7
CN1
CN2
DVD CD
R
O
/
-
DECODE BOARD
CN4
DVD KE
Y
BOARD

2． Main Board
Power supply troubleshooting
Display troubleshooting
Audio troubleshooting
Functionare troubleshooting

If
F
1/3
A
with 12
V
？
N
Y
Check fuse FI or external power E33/470μF/16V if Voltage is5 V
N
Y
Fuse burnt when power on？
N Y
N
Check if can power on
（via button or R/C）
Check power output
(U16,U18,U19)
OK Check F1 descending
Power supply network
Check if the second
Pin of U1 have 150
KHZ on-off signal
Y
LCD burnt out,
short-circuit
Y
OK
U1/
MP1410ES-LF or
D17/IN5822 has problem
L9/47Μh circle inductance
or solder problem
No damage but voltage
is higher
U1/
MP1410ES-LF the 4
th
pin
had Solder problem or U1
damaged
Check U21: if
power supply ,
reset,vibration
works normally
N
No damage but
voltage is lower
E33: power leakage or short circuit of
descendin
g
p
ower
Y
1) Power problem

2
)
Dis
p
la
y
p
roblem（dis
p
la
y
distortion/Mosaic）
M
osa
i
c
Check if the cable connected to panel
is right and works normally
Y N
Check if
panel is ok?
N Y
Check if the out
p
ut of U5
cable socket is ok?
Y
N
Change
panel
Check the power supply
And timer circuit of U5
Change the cable
which drives the
panel
Replace or repair this
part of circuit

3
)
、
D
is
p
la
y
p
roblem
（white screen）
White screen
Check if Voltage for panel is
ok?( depend on the selected panel )
N Y Y
Check G pole of Q24/AO34
01 has
the change of 3.3-0V or 5-0V
Y N YN
CN8 connecting defective
(provide have panel driving
voltage) or Q24 damaged
Check the circuit from the 98
th
pin of U21 to Q24
Panel defective or
drive cable for pane
has probleml
U5 defective or
power supply
abnormal
Check if U5 has signal output?

4
)
、
D
is
p
la
y
p
roblem
（black screen）
Black screen
Is there 5V backlight voltage
(
BLON
)
at CN19?
Y N
Check if inverter power supply
works nomally?
N Y
Replace Inverter
Check the circuit of Q26 or I/O
port of U21 (99
th
pin)
Check the
external power
supply

5
)
.Audio
p
roblem
（No sound）
N
o soun
d
Check if there is
Audio input
N
Is volume, MUTE
settings correct?
Y
Is there signal
output at CN11?
Check if voltage at the 7
th
pin of
U3/TPA1517NE is hi
g
her than 11
V
YN
N
Check if voltage at the 8
th
pin of U3 is higher or
equal
to
9.2V
Y
Check if the 1st and 9th pin
at U3 have input signal
N
Check if the 4TH and 6th pin
at U3 have output signal
N
Check if the 60th and 61th
pin
at
U3
have
output
signal
Y
Check
externa
l audio
device
R
eset
Check
external
speaker
Check the circuit
from the 104th
&105th pin of U21 to
the 8th pin of U3
Check is there audio imput
signal at U21:
PC: the 53rd & 54th pin
AV: the 49th& 50th pin
Scart:the 56th & 57th pin Check the
power
supply
circuit of
U3
U3
damaged
Check
U21:if
voltage
8V on 45th
pin is ok
or U21
damaged
Check
circuit
between
Audio
input jac
k
and U21
N
Y N
Y
Check
output
between U3
and CN23
N
N
Y
Y
Y
Check
the circuit
from the
60th &61th
pin of U21
to the 1st
A
nd 9th
pin of U3

6
)
Functionare （TV
Video）
TV no channel scan/no video
N
Check if RF imput signal is ok?
Y
Check voltage at the 7
th
p
i
n
o f T1/TEDE9-2B4A is 5V?
Y N
Y N
Y N
Y N
Y N
Check
external
RF
device
Check th
e
circuit betwee
n
24
th
& 25
th
p
i
n
of U21 and 11
t
h
p
in
g
of T1
,
an
d
p
ower su
pp
l
y
o
f
U21
T1
damaged
Check/re
p
air
the
peripheral
circuit
Check I2C
circuit( connec
ted to the 108
th
& 109
th
pin of
U21 TDA15021H
Repair
R267/0 Ω
Check the
step-up
circuit of
the power
supply pin
Check the
power
supply
circuit of
the pin
Check voltage at the 9
th
pin o f
T1 is 33V?
Check voltage at the 3
th
pin o f T1 is 0V?
Check: is there I2C data at the 4
th
&5
th
pin o
f T1?
Check is there signal at the 11
th
of T1 ?
Check voltage at the 1
st
pin o f
T1 is 1.5-4.1V?
YN

7
)
.Functionare（TV
Audio）
TV no sound，but have
video
Check if audio is ok under PC/AV
modes
N
Y
Check is there signal at the 2n
d
pin of
SAW2/AF389A2D
Refer to “ No sound ”
checking process
1. SAW2 damaged
2. U21: the 29
th
,30
th
pin have solder
problem
3. U21
p
ower su
pp
l
y
problem
4. U21 damaged
Check if the
circuit between
the 2
nd
pin of
SAW2
and
C133/0.01 μ F or
C133 is damaged
N
Y