93
Troubleshooting
No Raster
Is Power LED on Control Panel on?
Is Red LED Blinking on SMPS?
Find which LED fails to light or dims first on SMPS.
D949-SMPS STBY +11v
Check D918,I906,I007,I009
D931-SMPS SW +5v
Check D918,I907,I011,I012
D927-SMPS STBY +7v
Check D918,I905,I008,I010
D912-SMPS SW +29v (Audio)
Check E992,D910,IC01
Turn off power wait (3) seconds, turn ON carefully
inspect all Green LED’s on SMPS.
Did all 5 LED’s turn off at the same time?
Is voltage at pin(4) of I901 14v-18v?
Check D904,R905,R906,C907,F901,R902
No
Check I901,D961,R918,R919,Q901
Replace E991
Has protector E991 blown?
Does raster appear with G and K of
Q905 shorted?
Replace I901
Check R918,R919
Yes
No
Yes
Replace Q905
Check Q905,D921,D908,I902,Q902,D923
No
No
Yes
No
Is Click of Relay heard
Is the voltage at pin(51) and (33) of I0013.3v?
Check Q029,D035,L004
Is voltage at pin(23) of I001"AC Clock" in?
Is Voltage at pin(53) of I001 low?
Is the voltage at PQS2 pin(1) 7volts?
No
No
Check I001 pin(54)
Does reset occur?
Replace I006
Replace X001
Check I002
Replace I001
Check I001 pin(63)
Is 1.6v present?
Check I001 pin(62)
is 4mhz present?
Check Q008,Q009,I904,D909
Check Q003,Q004,D922,S901,Q002
No
Yes
Yes
Replace I001
No
D927-SMPS STBY +7v
Check D918,I905,I008,I010
Yes
Yes
No
Yes
No
No
Yes
Yes
No
No
Yes
Yes
Yes
Yes
To page ____
Inspect Red LED (DP37) on Deflection, Blinking?
Check EP98,DP11,Q777,QH01,TH01,DH11, on
deflection module.
Turn off power wait (3) seconds, turn ON ,carefully
inspect Green LED.
Does the Green LED tun off at the same time?
Is voltage at pin(4) of IP01 14v-18v?
Yes
Check PQD1 for 120vac
CheckVR923 on SMPS
Has protector EP01 blown?
Check IP01,DP04&5
RP10,RP11,RP12
Replace EP91
Check DP04&5, Rp02&3,CP05
RP10,RP11,RP12
Does raster appear with G and K of
QP01 shorted?
Check Q777,QH01,T751,T752
Are voltages of both ends of T751(primary side)
normal?
Is the base of Q751 normal?
No
Check T751,R754,R755
Check I701 pin(15) H-out,pin(8) Hvcc,
QP04,DP35,DP36
Check QP01/ Replace QP01
Yes
No
Yes
No
Yes
Yes
No
Check IP01,
RP10,RP11,RP12
No
Yes
No
No
Yes
Yes
No