Tatung VL5A9DA, Service Manual

Page: 15 / 89

15
II THE SCREEN is Abnormal , stuck at white screen, OSD window can’t appear, but
keyboard & LED was normal operation.
OK
Measured PCLK(pin 44 from CN201)
PVS,PHS (pin 40,38 from CN201)
Is there have any transition?
Pclk around 31.25MHZ ,PVS=60.09Hz ,
PHS around 50.4KHz ??(for input
signal=31K 60 Hz, and LED is green)
Check the bead-array & cap array(LP201
•
LP212
,CP201
•
CP212 was cold solder or bad)
NG , no transition
RE-do White-balance adjust
(see 4-2)
Change PANEL to new one
Check the PCLK at CN201 pin 44 ( or L201) , PVS at CN201 pin 40, PHS at
CN201 pin 38, Pdispe at CN201 pin 42, is there have any transition?
Pclk around 31.25MHZ ,PVS=60.09Hz , PHS around 50.4KHz ??(for input
signal=31K 60 Hz, and LED is green)
Check the bead-array & cap array(LP201
•
LP212
,CP201 • CP212 was cold solder or bad)
Measured TCLK(pin 141 from U200),PVS, PHS (pin
73,74 from U200) Is there has any transition?
Tclk around 31.25MHZ ,PVS=60.09Hz , PHS around
50.4KHz ??(for input signal=31K 60 Hz, and LED is
green)
And check Gmzan1 RGB output ( PD14
•
PD42) have an
transition?
No transition
C heck GMZAN1 BLOCK
No transition
Check RGB data from bead-array (PD14-1
•
PD42-1)
At CN201 ,Is there have any transition ?
Yes, have transition
Check panel power (R226) have DC voltage?
R226 ( Panel_P) =5V fro CPT,and 3.3V for
others panel
The maintainers must make sure the Power button
state is ON , ( check the LED should be green
state)
No
Yes, have transition
Check PERIPHERALS PANEL
BLOCK
NO voltage
Check all pin on GMZAN1 ( U200) for
cold-solder ?