Tyler TTV701-7 Service Manual

Service m an u al

二、Blank screen t roubl e shooti ng st eps:

NO NO

YES

YES

No

YES

Check the cathode of DI1(IN5819) if there have 10V voltage

Check

UI1(G5121)from the 6

pin have 5V voltage

Check th e circuit from

U15(MSD3393) of the 133th

pin to UI1(G5121) of the 6th pin

Check the UI1(G5121) peripheral circuit

And replace UI1

Check Q12 base

electrodeIf it is a

Check the circuit from Q12base electrode

to U15(MSD3393) of the 109 pin and

replace U15

Check the circuit from Q12

emitter electrode to back light, and
replace back light

三、Has image, no sound/low sound/distortion

YES

No

No

YES

Maximum volume，on USB/SD reading status, Use the

multimeter to test the pin 3/8 of U13 （SL6699）,whether
the speaker has noise.

Whether the speaker open circuit?

Replace speaker

Check the component from the 3/8 pin o f U13
to the pin 47/46 of U15，or repl ace U15
（MSD3393）

Test U13 peripheral

components or replace U13

五、AV input no image no sound

NO

YES

NO

YES

NO

YES

Check if AV input socket is normal?

Check if AV cable is normal?

Replace AV input socket

Replace AV cable

If no sound, check ,Check AV input socket circuit from audio frequency to the external

components of

U15 34/35/36/36 pin；N o image, check if video frequency to the external

components of U15 28, 29 pin is normal

Replace the related components

Replace U15

六、Snow screen/image not clear

YES

NO

NO

YES

NO

YES

Check if power supply -10V/+15V/+10V/+3.3V/5V on PCB sockets

are normal

Whether the cable of LCD screen loose?

Tighten the cable.

Check if the circuit from PCB socket to U15 (MSD3393) is normal

Check the abnormal power supply circuit.

Check the abnormal circuit.

LCD screen abnormal.

1 2 3

5 6 74

四、DTV no signal trouble shooting steps:

NO

NO

YES

NO

YES

NO

YES

NO

YES

Whether U6(R840) 11,18，24 circuit
+3.3V voltage normal.

Select the local color system and sound system, then

start auto channel scanning

Whether the circuit from
U15 104 pin to U6(R840) 11,18，24 pin
normal?

Check if the circuit component from U15 58,59 pinto

U6(R840) 6、7 pin is normal.

Replace related component

Check if the component of U15 49/50 pin and U6(R840) 17、16 pin is normal

Replace the related components

Replace U15 or U6

When channel scanning, check if the 48 pin voltage of U15 changed on 0-3.3V range.

Check th e power supply of U 15

51/52 pin and replace U15

一、No sound, no image, blank screen troubl e shooting steps:

NO Red ligh t on

NO

YES

YES

NO

NO

YES

NO

NO YES YES

Whether the power light is on?

Whet her the
I C2(ETA1483) +5Vpower out put

normal?

Check the electrical level of U11

（SC61A05）from 1st pin is low

Check whether the 12V input voltage
of IC2 (ETA1483)’s 2nd pin is normal

Check the
related
abnormal
circuit.

Check U9 software and Y2

crystal vibration circuit，o r

U15(MSD3393)

malfunctions.

Test the power s upply of

U15(MSD3393) 3.3V/1.8V/1.2 is

normal

Whether the green light on

when press POWER

button.

Check DC input jack and

AC adapter 12V

Test battery positive
electrode ： if have 4.2V

circuit is normal ,o therwise

replace U11

Check the circuit of U11 from 1 pin to the LED light.

And replace indicator lamp.

See 2nd

phenomenon: blank

screen

maintenance steps

Repair or replace the circuit of

IC2

(ETA1483)

七、USB not reading

NO

YES

NO

YES

八、SD card not reading

NO

YES

NO

YES

NO

YES

Replace the socket.

Whether the socket normal?

Test USB ① pin 5V power, check the circuit
from USB ? ? to U15(MSD3393)’s 123,124 pin

Check the power supply of
USB socket and other
component.

Replace U15 (MSD3393)

Replace the socket.

Check if the socket is ok?

Test SD socket each pin to the related route
of U14（MA8121K）is Ok.

Maintenance related corresponding circuit

Test U14（MA8121K）18 pin if there have 5V power supply

Repair the related circuit
components from U15 110 pin to
U14 18 pin.

Repair the components from U14 23,24 pin to

U15 125，126 pin ，or replace U14、U15

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