Read Sharp PG-M20X (serv.man10) Service Manual online
25
PG-M20X
TROUBLE SHOOTING TABLE
Yes
No
Checking of Basic Operation
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
Yes
No
Does the video input operate
normally?
normally?
Does the DVI input operate
normally?
normally?
Do the component input/DVI input
operate normally?
operate normally?
Does the RGB input operate
normally?
normally?
Is the user menu displayed?
Does the cooling fan rotate and
does the lamp light up?
does the lamp light up?
Go to "Checking of Power Unit".
Go to "Checking of Sub-microcomputer
and Its Periphery"
and Its Periphery"
Go to "Checking of Lamp Lighting-up"
Check the formatter circuit and
its periphery.
its periphery.
Check IC8013 (AD) and go to
"Checking of RGB Input".
"Checking of RGB Input".
Is there input signal at pins
(8), (17) and (23) of IC8013?
(8), (17) and (23) of IC8013?
Check IC8015 and peripheral
circuit.
circuit.
Go to "Checking of Video
Input". Is there input signal at
the emitter of Q8002?
Input". Is there input signal at
the emitter of Q8002?
Check IC8015 and its
peripheral circuit.
peripheral circuit.
No
Check IC3851 and its
peripheral circuit.
peripheral circuit.
No
Check IC3502 and its
peripheral circuit.
peripheral circuit.
Does the POWER LED light up or
flicker in red or green?
flicker in red or green?
End
Does the set operate by the set's
key or the remote controller's
power key?
key or the remote controller's
power key?
26
PG-M20X
Yes
No
Checking of Power Unit
Are connectors in the power unit
completely inserted?
completely inserted?
Yes
No
Is the lamp door closed
completely?
completely?
Close the lamp door completely by
screws.
screws.
Yes
No
Is the bimetal switch turned off?
Replace the bimetal switch, or rest
it by pressing the red button.
it by pressing the red button.
Yes
No
Is AC voltage applied across relay
RL7001?
RL7001?
Replace F701.
Yes
No
Is there DC voltage of about 6V at
pin (1) of CN7002?
pin (1) of CN7002?
Check Q7501, Q7502 and Q7503
and their peripheral circuits. If any
circuit is damaged, replace it.
and their peripheral circuits. If any
circuit is damaged, replace it.
Yes
No
Is there DC voltage of about 370V
across CN702?
across CN702?
Check the circuits connected to the
primary side of T701. If any circuit
is damaged, replace it.
primary side of T701. If any circuit
is damaged, replace it.
Yes
No
Is there rated voltage at the output
terminals of CN7001 and CN7102?
terminals of CN7001 and CN7102?
Check the circuits connected to the
secondary side of T701. If any
circuit is damaged, replace it.
secondary side of T701. If any
circuit is damaged, replace it.
Check the PWB circuits of relevant
output sides.
output sides.
Insert the connectors CN702,
CN704, CN7003, CN7001,
CN7004 and CN7101 completely.
CN704, CN7003, CN7001,
CN7004 and CN7101 completely.
27
PG-M20X
No
Lamp Does Not Light Up.
Yes
Is an appropriate voltage supplied
to SC9002?
to SC9002?
No
Is there the 180-Hz pulse signal at
pin (1) of P9002?
pin (1) of P9002?
Is any of SC9001, SC9002, P9002
and P9003 connectors
disconnected or in poor contact?
and P9003 connectors
disconnected or in poor contact?
Yes
Insert the connectors completely.
No
Go to "Checking of Input PWB"
Go to "Checking of Input PWB"
Go to "Checking of PC I/F unit"
Yes
Go to "Checking of Lamp" and
"Checking of Ballast"
"Checking of Ballast"
Yes
Is the color wheel rotating?
No
Go to "Color Wheel Does Not
Rotate."
Rotate."
Yes
Is the signal at pin (10) of IC9101
at High level?
at High level?
No
Are the signals at pins (69) and
(70) at High level?
(70) at High level?
Yes
No
Yes
Is the signal at pin (9) of IC9101
at High level?
at High level?
No
Trouble with IC9003
Trouble with 1C9101 or its
peripheral part.
peripheral part.
Yes
Is there the 180-Hz pulse signal at
pin (2) of P9003 when no input
signal is given?
pin (2) of P9003 when no input
signal is given?
No
28
PG-M20X
Lamp does not light up.
Yes
Yes
Is the cooling fan rotating?
Check the socket
Check the power circuit.
No
Check the power circuit or the fan
circuit on the key/input PWB.
circuit on the key/input PWB.
Yes
Is the color wheel rotating sound
heard?
heard?
No
Check IC3101, the motor driver
circuit and their periphery.
Check the waveform of SC3101.
circuit and their periphery.
Check the waveform of SC3101.
No
Normal
Abnormal
Is the lamp discharging sound
heard?
heard?
Yes
Yes
Is DC 34V voltage applied across
the ballast power?
the ballast power?
Check the ballast power.
No
Check IC9101 and its periphery
on the formatter PWB.
on the formatter PWB.
No
Is voltage higher than 3.5V applied
to pin (19) of P9002 on the
formatter PWB?
to pin (19) of P9002 on the
formatter PWB?
Yes
Replace the color
wheel.
wheel.
Check the
formatter PWB.
formatter PWB.
No
Replace the lamp.