Re: Vizio M557-G0 vertical red lines
Thanks for the attempt though....
mightymos
New Member
Last Activity: 07-08-2022, 11:56 PM
Joined: 06-23-2022
Location: Texas
-
Re: Vizio M557-G0 vertical red lines
I initially ruled it out since they board seems to be getting +18V and fault line on power supply shows high level (good) (but guess that just means led drivers are okay). I'll try to check supply voltage on main board, tough without a schematic. Any advice where to start?...Leave a comment:
-
Re: Vizio M557-G0 vertical red lines
Thanks so much for taking a look....Leave a comment:
-
Re: Vizio M557-G0 vertical red lines
Hey sorry, any of my voltage measurements in the other post seem suspect? Did I miss any measurements?...Leave a comment:
-
Re: Vizio M557-G0 vertical red lines
I finally paid attention to silkscreen and noticed labeled test points.
AVDD 15.12 V
VSS0 0 V
VGHD 24.8 V
VGH 24.8 V
VSSG -7.9 V
VCC 3.3 V
V3D3 3.3 V
0_TCON 1.8 V
1_TCON 1.1 V
V12 12.2 V...Leave a comment:
-
Re: Vizio M557-G0 vertical red lines
As far as I can tell I reseated cables and they seem okay.
I can get TV to respond to button presses for power and maybe display changes when I push other buttons but no intelligible display.
I have the 55T32-C0L board.
The problem is I can only find one datasheet for RT7277 step down converter, though other switching regulators seem to be present. There's one other datasheet found for serial flash.
The voltage feedback divider is a little different than datasheet and uses three resistors, two in bottom...Leave a comment:
-
Vizio M557-G0 vertical red lines
See attached photo for symptoms.
Supply board produces +18V on output pins and shows no fault with ~3V on fault pin. Backlights come on.
I replaced two 220uF capacitors on main board because plugs might have popped a little underneath (hard to tell) but no change in symptom. Main board has two UART headers which I soldered connectors onto, but do not see activity on either with scope.
I've tried wiggling connectors around unit when powered on but no change in symptoms.... -
Re: New Members - please post your introductions here
Greetings all, electrical engineer from Texas. Will be posting a thread with screenshots of a VIzio M557-G0 with vertical red lines. Trying to diagnose.Leave a comment:
No activity results to display
Leave a comment: