Akira L2655 Schematic

AKIRA

• SERVICE MANUAL

SERVICE MANUAL

• L 2655

-- Power category troubleshooting

-- Display category

troubleshooting

-- Audio category troubleshooting

-- Function categories troubleshooting

CV109H_V2.0 Common

troubleshooting

Standby, the board test points TP11 whether 5 V?

main board test point TP5 if have 3.3V

，

test point

TP13 if have 1.25V

？

Normal turn on

Power chip LDO (U1)

whether the work , output

voltage whether 2.5V, or

load short-circuit

After turn on

，

test point TP2 if have

5V ,test point TP2 if have 5V

，

test

point TP9 if have 2.5V

Y

N

Figure 1 Power category

troubleshooting

Y

N

OK

check U3 U10 power network

AC input is normal

The replacement

of power

N

check power module

Y

OK

screen noise or

screen black

（

but backlight is on

）

screen driver wire if correct

connect well if OK

change LCD if normal

change screen

driver wire

Y

N

Change LCD

N

Y

check output network

J8 screen driver socket part if normal

Y

check U15

power and clock circuit

IC LVDS output pins if

short，open

Figure 2 shows that

part (

part ( Huaping

Huaping

Huaping )

)

N

Check the power VCCPanel LCD whether 5V

software if match

upgrade matching

software again

N

Change and fix this part circuit

screen black

Check Inverter output voltage

whether normal

？

check the Inverter power

J5 ’ s 1 pin output voltage

whether 5V

？

check & fix power circuit

N

N Y

Y

check & fix this part control

circuit

Inverter

or connected wire

doesn't work

Figure 3 shows that some

(blank screen)

No sound

if have audio signal input

AMPLIFICATION power if normal

check

external

audio

equipment

：

AMPLIFICATION

power circuit

U7

（

TPA3123D2）5/6

pin if have signal input

N

Y

N

volume 、MUTE setup

if normal

Setup

again

J1 、 J2 if have

signal output

Y

N

Check

external

speaker

check & fix

AMPLIFICATION

power circuit

NY

Y

test U22 audio output pin

if have signal output

check & fix U22 to U7 meddle part network, include U23 operation circuit

check & fix

network

From U22

to U7

Figure 4 audio part (silent)

Y

check power

supply circuit of

U22 ’ s Pin8

And U23 ’ s Pin8

test U22 ’ s Pin1-7

if have signal output

N

TV doesn ’ t search /no picture

Figure 5 function part

（

ATV

video troubleshooting

）

External RF input signal if normal

N

check & fix

external

RF

equipment

Y

test turner Pin 3

if have 5V

check &

fix this

pin power

network

U12

circuit

Y

N

test tunner pin8 and pin9 if have I2C data

check

I2Cnetwork

(U15 ’ s

205/206pin)

N

Y

test Tunner pin17 if have CVBS signal

N

Check U15

(MSD109BL)

Pin46 and Pin47 and filter

network

U26 failure

change turner

Y

U18 ’ s power supply if normal

test U26 ’ s pin7 input signal if normal

change

Crystal

Oscillator

、

TDP9886 and

U17 ’ s circuit

check U12 ’ s

circuit and

power

supply

network

N

Y

TV no sound, picture is on

PC AV if have sound

N

Y

refer to “ no sound ”

maintenance

processes

Figure 6 function part

（

ATV no sound

）

test U18 ‘ s pin12 if have audio signal

N

check U15 ’ s (MSD109BL)

Pin 46/47

and filter

network

Y

change

turner

U18 ’ s power supply if normal

U26 ’ s Pin7 output signal if normal

Y

N

change

Crystal

Oscillator 、

TDP9886 and

U20 ’ s circuit

check U12 ’ s

circuit and

power

supply

network

Y

N

TV no search / no picture

Figure 7 function part

（

DTV

video troubleshooting

）

External RF input signal if normal

N

check & fix

external

RF

equipment

Y

test turner pin3 if have 5V

check &

fix this

pin power

network

U12

circuit

Y N

test U26 Pin5 and pin6 if have I2Cdata

check

I2Cnetwork

(U15 circuit,

U15 ’ s

205/206pin)

N

Y

test U5(ZL10353) — TS stream if have signal

？

N

Check U15

(MSD109BL)

networks

Y

test U5 ’ s pin30/31 if have signal input

N

Y

U26 doesn't

work

change turner

U8 ’ s Pin2-4 output voltage if 1.8V U2 ’ s Pin2-4 output voltage if 3.3V

U5 ’ s power supply circuit if normal?

Check U5

、

crystal etc.

correspond

circuit

TV no sound, picture is on

PC AV if have sound

N

Y

refer to “ no sound ”

maintenance

processes

Figure 8 function part

（

DTV no sound

）

test U22 ‘ s pin12 if have audio signal

check U15 ’ s (MSD109BL)

Pin 74/75 and filter

network

Y

N

check

amplifier

U22 ’ s circuit

PC

Picture not

at the center

color less,

color cast

Picture

Jitter

no signal

Automatically

perform

Adjustment order

U15(MSD109BL)

R.G.B input

signal if normal

system setup

wrong

Reset again

Y

N

VS,HS signal

if rules, stability

check VS.HS

circuit

OSD setup doesn ’ t match reset again or input Mode not support

check VS.HS

circuit

Y N

Figure 9 function part

（

PC

）

VGA socket

connect if

OK

？

VGA socket

connect if

OK

？

check VGA input circuit

Y

SCART RGB

、

SCART Video

、

Y/C

SCARGT

color less,

color cast

All non-signal

System set

incorrectly

re-reduction

Check SCART RGB input network

U15 (MSD109BL)

electricity and

crystal Y2

U15 (MSD109BL) of the RGB

input signal is normal

Y N

Figure 10

functional part

(SCART, AV, SV)

SCAR socket

contacts are good

HDMI

no picture

picture on,

no sound

refer to “ power “

maintenance processes

check HDMI input network

check EEPROM

circuit and

components

U15 (MSD109BL)

related to the HDMI

network

Y

N

Figure 11 function part

（

HDMI

）

PC if have sound

Y

N

refer to “ no

sound ”

maintenance

processes

Figure 12 functional part

of PCMCIA cards

CI inserted under the PCMCIA card did

not mention whether CI MODULE INSERTED

Into the menu, read

the information CI

Check power supply VCC-PCMCIA,

check Pin17 and pin51 output

voltage if 5V

CI Module

Inserted

CI Module

Removed

Y

N

Y

N

CI Card insert

Change CI card

Check CI Card

network

CI Card remove

Akira L2655 Schematic

Specifications and Main Features

Frequently Asked Questions

User Manual