Vizio M550NV Shuts down at startup logo flashes then repeats

[lawnjobbers]

I have a M550NV that won't make it past the startup. It was possibly hit by lightening. Logo flashes between Amber and White, then startup logo displays on screen (backlight works), about 1min 30 secs no response from remote or side control knob. I need any help I can get. I have some experience in fixing flat screens. All capacitors look good, no bubbles or leaks. Backlight and Readings on the Power Supply are as follows

18V Standby = 0.00V, On = 18.17V
18V Standby = 0.00V, On = 18.17V
GND
GND

PWM Standby = 0.00V, On = 3.34V
NC =
BL_ON Standby = 0.00V, On = 3.33V
POWER_ON Stanby = 0.00V, On = 3.19V

12V = Standby = 0.00V, On = 11.77V
12V = Standby = 0.00V, On = 11.77V
12V = Standby = 0.00V, On = 11.77V
GND
GND
GND
GND
5V Standby = 5.15V, On = 5.15V
5V Standby = 5.15V, On = 5.15V
5V Standby = 5.15V, On = 5.15V

5V Standby = 5.15V, On = 5.15V
5V Standby = 5.15V, On = 5.15V
5V Standby = 5.15V, On = 5.15V

Bottom 450V Capacitor Standby = 102.8V, On = 343V
Top 450V Capacitor Standby = 102.8V, On = 343V

[tom66]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

The most common issue on this set appears to be an issue with the EEPROM causing random crashes.

[randtek]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

That is a classic symptom of a corrupted/failed EEPROM on a Visio. Tom is probably correct.

[tom66]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

I am thinking of investing in a flash programmer (I already built an EEPROM programmer) to fix TVs with these issues. However, I have no idea where these companies selling flash chips at £20 each are getting the firmware files from? If I knew I would offer them for free download! Only ever found one, for a Toshiba...

[Th3_uN1Qu3]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

IIRC Vizio offers firmware upgrades to the customer for fixing/improving some functionality, in the form of USB drives that they supply, you plug into the TV and it updates the firmware. I remember one user here reporting that he got one, and it made things worse.

Most commonly tho, the firmware files are simply dumped from working sets of the same kind. Dumping the EEPROM/Flash of any new/unknown TV that arrives in the shop has been a long-time practice for TV repair shops.

[lawnjobbers]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

So is this something I can replace, I'm very mechanically inclined, have experience with replacing capacitors and I can solder. Would I be better off replacing a board? Does everything sound within spec?

[cashkennedy]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

I dont see the eeprom chip for that model for sale on ebay, there is a guy selling a bunch of similar vizio models eeprom chips, so you could ask him if he can get it. (they run around 20 dollars for the chip)

Soldering that in is medium - hard difficulty. You would need a good soldering iron, and some patience, and some skill so on, by no means impossible, or the hardest parts to solder. If you can find a working main board for 40 dollars or less i wouldnt waste your time replacing the eeprom.

Edit: Looks like boards for these are rare, so fetch a high price. There is a repair service for 100 for the board, but if your fairly good at soldering you might want to search for a eeprom to replace the bad one with instead of shelling that out.

[lawnjobbers]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

How sure are we it's the EEPROM. I can get a Main Board for $150, but I'd like to be reasonably sure

[ecking767]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

How sure are we it's the EEPROM. I can get a Main Board for $150, but I'd like to be reasonably sure

If your M550NV LED TV is stuck on the "VIZIO LOGO" then that a EPROM problem, the M550NV is a smart TV and the EPROM chip is a 16MB chip and most likely is a TSOP-48. Excellent soldering skill will be need if you was able to buy a copy of an EPROM for your TV. Copying your EPROM with those "Internet APPS" maybe copy protected.

you need to buy a replacement main-board or call vizio to see if they will offer to re-flash your mainboard

[tom66]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

I don't think we care about copyright that much. As long as we do not redistribute the files, there should be no issue. Also, I would expect more than 16MB for app storage, especially when you consider all resources (images, program, strings.) Maybe a second gigabit flash or something.

[ecking767]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

I don't think we care about copyright that much. As long as we do not redistribute the files, there should be no issue. Also, I would expect more than 16MB for app storage, especially when you consider all resources (images, program, strings.) Maybe a second gigabit flash or something.

Well, I have seen alot of Vizio smart TVs and every one I came cross was using a 16mb flash. I have a Vizio M470SL LED TV on the work bench and its a smart TV and the EPROM is 29F16G08CBACA. To copy this EPROM the programmer will cost about $600.00 usd. and about 30.00usd for the adapter need for the chip itself.

Also the TV serial number is record in EPROM, If you check the Menu under the help section then system information.

[tom66]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

Must be pretty basic bare bones apps then. It would cost $600 if you bought one, sure. But who's to say you can't modify an MCU board? I've got a board here which would easily be capable of the task. If I had flash files I would have no issue in offering programming services for small fees.

[Louis82]

Re: Vizio M550NV Shuts down at startup logo flashes then repeats

Tom. Have you been able to find the files to program the EEPROM for Tv model M550NV ? Or, do you have any of these EEPROMS for sale ? I have a tv on work bench with the orange light that does not change to white (not turning on).

Thank you!