Sharp LC-32WD1E/S/RU Service Manual page 70

LC-32WD1E/S/RU, LC-37WD1E/S/RU, LC-42WD1E/S/RU, and LC-32/37/42WT1E
Power unit operation check (SHPWR0000137)
Are the power cord and extension cable in
the unit properly connected?
Is F1 normal ?
Is F2 normal ?
Is a 390~450V voltage on the C8?
Is there power down signal (3~3.4V) on the
PIN 3 of CX400 between the PIN 2 of
CX200?
Does the PSU_STBY Voltage from system?
Continued on next page.
Yes
Yes
Yes
Yes
Yes
No
Connect the power cord and extension cable
properly, and turn on the power again.
No Are both components (VR2 and VR3) Low
impedance when checking their resistance
values?
Replace F1
No
Is it low impedance when checking the
C5&C8 Resistance values?
Replace F2
No
Is it not enough 390Vdc?
Check PFC stage, including D5,L2,Q2,Q3
and IC1
No
Is there 3.3V output on the C94
Yes
To check Q8 and PC5.The
Q8 and PC5 was conducted
when the
applied to PSU.
6-39
Yes
Yes
Yes
No
Replace
PSU.
AC voltage