Sharp PG-M20S (serv.man11) Service Manual ▷ View online
28
PG-M20S
PG-M20X
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 IC3852 and its
peripheral circuit.
peripheral circuit.
No
Check IC3852 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?
29
PG-M20S
PG-M20X
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
Does the temperature
fuse function?
fuse function?
Replace the fuse as well as its
harness.
harness.
Yes
No
Is AC voltage applied across relay
RL701?
RL701?
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 CN702 and CN7102?
terminals of CN702 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.
30
PG-M20S
PG-M20X
PG-M20X
No
Lamp failure to light up
(formatter unit)
Yes
Is there the specified voltage at
pin (15) of SC9002?
pin (15) of SC9002?
No
Is there the 180-Hz pulse signal at
pin (1) of P9002?
pin (1) of P9002?
Is any of the SC9001, SC9002,
P9002 and P9003 connectors
disconnected or in poor contact?
P9002 and P9003 connectors
disconnected or in poor contact?
Yes
Insert the connectors completely.
No
Is there the specified voltage at
pin (11) of P3002?
pin (11) of P3002?
No
Check the fan circuit
(near IC2101) on the
KEY PWB.
(near IC2101) on the
KEY PWB.
No
Check the power unit.
Are there the specified voltages
at pins (23) and (24) of P3003 on
the input PWB?
at pins (23) and (24) of P3003 on
the input PWB?
Go to "Checking of PC I/F unit"
Yes
Yes
Check the lamp and ballast unit.
Yes
Is the signal at pin (10) of IC9101
at High level?
at High level?
No
Are the signals at pins (69) and
(70) of SC9001 at High level?
(70) of SC9001 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 IC9101 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
Yes
31
PG-M20S
PG-M20X
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 340V voltage applied across
the ballast power?
the ballast power?
Go to "Lamp failure to light up
(formatter unit)".
(formatter unit)".
No
Replace the color
wheel.
wheel.
Check the
formatter PWB.
formatter PWB.
No
Replace the lamp.