vizio gv47l amber logo no power on.

[Horty24]

Hi guys, I have a vizio gv47l that does not want to power on.
Vizio logo stays amber/ orange.
No clicking sound when power cord plugged in.
No backlight.
Can not power tv on by pressing power button on front panel.
Tested 5v, 12v, 24v from PSB results
5v = 5.3
12v = 0
24v = 0

Known causes are power supply board or main board.
To verify, does the main board tell the power supply to send power?
If so the PSB may be ok but the MB may be faulty and may not be sending signal to PSB to send 12v and 24v?
What else can I troubleshoot?

[budm]

Re: vizio gv47l amber logo no power on.

You need to look at the power supply board connectors, look for PS_ON pin, that is the signal from the main board to turn on the PFC Voltage booster circuits and the 12v/24v power supply circuit. That pin should have voltage from 2v ~5V when you hit the power switch. Post good clear pictures of the boards so we will know what we are dealing with. You should also read the Basic LCD TV troubleshooting guide.

[Horty24]

Re: vizio gv47l amber logo no power on.

Here are pics of PSB and main board.

[budm]

Re: vizio gv47l amber logo no power on.

Take good close up of those connectors on the power supply board so we can read the labels of the connector's pins.

[Horty24]

Re: vizio gv47l amber logo no power on.

I'm getting 69.0v on PSON. Way over, maybe that's why it's in standby mode.
Now what should I check on the main?

[Horty24]

Re: vizio gv47l amber logo no power on.

I Removed The Main Board And visually Inspected For Burn Marks Or Bad Solder.
Everything Looks Normal And Clean. I Can Now Troubleshoot With ENM But What Should I Check? Fuse At F1, F2, F3 Are All Good.

[budm]

Re: vizio gv47l amber logo no power on.

You better check your meter first, 69V would have blown up just about every thing on the power supply board PS_ON circuit and on the main board. There is nothing on the main board that generate that much voltage!

[Horty24]

Re: vizio gv47l amber logo no power on.

Lol Ok I'll Check Again. So You Need A DC Reading From PSON with Cable From The Main Board Connected. The Only Thing It's That My Power Button Does Not Try To Turn The TV On. I Don't Even Get The Front Buttons.. Power,Channel,Volume Illuminated. So I May Not Be Able To Get A Reading While Pushing The Power Button.

[budm]

Re: vizio gv47l amber logo no power on.

At this point, you will need to check the voltages of all the 3-pin voltage regulators on the main board, they will be labeled with something like 1117-xx, or 1117.
Follow the instructions:
https://www.badcaps.net/forum/showth...999#post300999

[Horty24]

Re: vizio gv47l amber logo no power on.

Ok PSON power off = 00.01v
PSon power supplied = 00.06v
Ill check the voltage regulators now.

[Horty24]

Re: vizio gv47l amber logo no power on.

Here are all the readings of the regulators on the main board. This is with power supplied
All regulators are IN top pin OUT middle pin ADJ bottom pin. Sequence read outs are in this order below.

U4 6IBL 1733L
In 5.11
Out 3.28
Adj. 0.00

U5 AMC117 F0635J
3.28
1.94
.69

U6 6IBL 1733L
5.11
3.28
0.00

U7 6I1L 17-18L
.45
0.0
0.0

U8 6IBL 1733L
.34
.45
0.0

U9 6I1L 17-18L
.45
0.0
0.0

U10 6I1L 17-18L
.45
0.0
0.0

U16 6G1L 17-25L
.35
.63
0.0

U18 AMC1117 F0635J
.45
0.0
0.0

DU1 AZ7805T E1 620J35
0.0
0.0
0.50

DU2 6IBL 17-33L
.38
.66
.00

DU3 6G1L 17-25L
.38
.01
0.0

DU4 AMC1117 F0635J
.80
.01
0.0

[budm]

Re: vizio gv47l amber logo no power on.

U4 6IBL 1733L: 3.3V FIXED REG OK
In 5.11
Out 3.28
Adj. 0.00

U5 AMC117 F0635J : Adj reg 1.25 + .69 = 1.94 = OK
3.28
1.94
.69

U6 6IBL 1733L; 3.3V Fixed reg, OK
5.11
3.28
0.00

U7 6I1L 17-18L: 1.8V Fixedn reg, low input, need to find out why
.45
0.0
0.0

U8 6IBL 1733L3.3v Fixed reg, low input, need to find out why
.34
.45
0.0

U9 6I1L 17-18L: 1.8V Fixed reg, low input, need to find outwhy
.45
0.0
0.0

U10 6I1L 17-18L: 1.8v Fixed reg, low input, need to find out why
.45
0.0
0.0

U16 6G1L 17-25L2.5V Fixed reg, low input, need to find out why
.35
.63
0.0

U18 AMC1117 F0635J: low input, need to find out why
.45
0.0
0.0

DU1 AZ7805T E1 620J355v reg, no input due to no 12v
0.0
0.0
0.50

DU2 6IBL 17-33L:3.3v Fixed reg, low input, need to find out why
.38
.66
.00

DU3 6G1L 17-25L:2.5V Fixed reg, low input, need to find out why
.38
.01
0.0

DU4 AMC1117 F0635J:Adj reg, low input, need to find out why
.80
.01
0.0

Need to locate surface mounted fuses on the main board, I can see 3 of them (white surface mounted fueses) by the white connector that goes back to the power supply baord

[Horty24]

Re: vizio gv47l amber logo no power on.

those Three Fuses Marked F1, F2,.F3 All Showed Continuity. Another Post Indicated To Test For OHMS?

7) Power off and unplug lcd. Wait 3 minutes. Then put your multimeter to 200 ohms and measure the resistance of the 2 fuses circled in red. If they are good, both some measure less than 1.0 ohms.

[budm]

Re: vizio gv47l amber logo no power on.

You can test the DC voltage on both ends of the fuse with ref to the chassis, or set the meter to Ohm mode and check the resistance, they should be less than 1 Ohm.

[Horty24]

Re: vizio gv47l amber logo no power on.

F1 rated @ 1.5A= .4OHMS, 5.13v at both ends.
F2 rated @ 1.5A= .4OHMS, 5.13v at both ends
F3 rated @ 3A. = .4OHMS. 0.63v at both ends.
Looks like failed fuse at F3?

[budm]

Re: vizio gv47l amber logo no power on.

F3 is fed by 12V so I do not expect any voltage at that fuse since the 12v/24v power supply are not turn on by the main board yet. So I do not know why you are not getting the 5V feeding some of those regulators.

[Horty24]

Re: vizio gv47l amber logo no power on.

Could it be that my power on board is faulty or not relaying the info to main board?
Reason I ask is that the power,vol,channel,source board does not illuminate or respond once the power is supplied.

[budm]

Re: vizio gv47l amber logo no power on.

The power board supplies the 5V for the microcontroller on the main board to run, when the power switch is activated, the main board will then send the signals to the power board to run on the 12V (for audio amplfier circuits), 24V for the backlights inverter board, and backlights on and backlights dimming signals to the inverter board. So right now the 5V is working but the main board is not working due to missing voltages. It is going to be real indepth to find out exactly which components are bad on the main board.

[Horty24]

Re: vizio gv47l amber logo no power on.

Thanks for your help Bud. If you have ideas on what to check next I'm Willing to try.

[Horty24]

Re: vizio gv47l amber logo no power on.

Bud I might not have explained my post #17 clearly. My fault. Could I not be getting the PSON power because of

This 5vdc is used to power the Processor and the Infrared remote receiver module which will be waiting for the command from the remote control or from the power switch, when the Power on command is received, the Processor will send the turn on signal (3.3~5vdc) to the power supply module (PSON pin) to the switch on the main 5vdc for the rest of the logic and Tuner circuits,

My infrared remote module does not illuminate or respond to any of the settings
( power,channel,volume,source) . Maybe why in not getting correct readings on he regulators since The signal is not being sent? I don't have the remote control for the tv.