Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

[reessi]

Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

This came to me with alot of water damage on the power supply board so I replaced that board from ebay.

Now it powers on displaying the Hitachi logo then off. Can keep turning on like this.

When first plugged the standby leds flash slowly red/blue and it displays the logo without me pressing the power button, then shuts down after 3 seconds and displays red led.

Now if I press power button it will display logo again but this time when it shuts off the leds flash alternating really fast.

I can keep turning on if I want but always shuts off.

Anyone know what the led flashing means, are they error codes?

I have checked the power supply caps/diodes with meter & esr meter, all seam fine. I have checked output voltages with the schematic. They seam to be correct.

I would like some explanation though, the power supply seams to only have a 12v output and it always outputs even when off. Upon turn on there are no other voltages, it turns the leds on through a seperate connection.

This is whats in the schematic as well. I am confused if the 12v is always on then what is the signal for standby-on for? There is a seperate signal for backlight on. Also what confuses me is when the board is removed and powered the standby signal is at 0v. But when in the set it is as 2.6v while off and then 0v when it turns on so does that mean its on when powered out of the set but again what is actually on as the 12v is always on anyway!!

Thhe backlight on pin is at 0v and then 3.2v when leds light.

The board according the schematics has another power block connecter and this has 24v but my connector is clearly marked as nothing connected to that pin.

Many thanks.

[Alastair E]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

Corrupted f/w, vestels are such utter turds!

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

Thats what I read in another thread on here!

Can I re-flash do you think?

Cheers.

[vinceroger69]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

on the back of the tv theres usually a white sticker saying what the lcd panel number is can you find it and let us know what it is

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

ves420undl-20-n03

Cheers.

[vinceroger69]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

is there any other numbers on the mainboard usually on stickers as well

[vinceroger69]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

this is cheap but not sure if its a match
http://www.ebay.co.uk/itm/MAIN-AV-BO...kAAOSwlaxWOL-I

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

Yes, alot, on a white one - 10093507 23225762 428 42" (one line),
27334079 DIJ,
362J5,

Some more on a blue one half under the white one, do you need?

Cheers.

[vinceroger69]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

i have had a quick look for a eeprom or dump of it and cant find any im not sure if that mainboard will work and how many of the numbers need to match maybe Alastair E or reece can advise

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

Yes I had a look earlier on ebay, Can you say from the symptoms that you would be pretty sure its a corrupted firmware? Do you know which is the important number to match. For instance if I bought a Digihome one what would be the problem, are we matching the exact model of panel to the firmware on the board or just the panel size? And can I re-flash this board?

Many thanks.

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

Also do you know what causes the firmware to corrupt?

Cheers.

[vinceroger69]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

if you say put a diffrent brand i guess on start up it will say digihome? ive not tried it have you got any freeze spray as sometimes you can get the eepronm cold it will start up ok as this sets water damaged you dont really no i guess what other faults it may have ie got on to tab bonds etc im still learning my self but i always match replacement mainboard to the panel sticker as people have issues with display being upside down etc
hopefully a more experienced member will advise what needs too be matched on this series mainboard

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

The picture is fine for the 3 seconds its on, I checked the M/B under the microscope, no sign of water damage, could have been damaged I guess when he PSU blew, was no output from it when I got to it but alot of corrosion on psu. I havent got any freeze spray, I could get some tomorrow, why do you think that would help the Eprom? Are you thinking dry solder joints although dont people normally heat up for that?

Cheers.

[Alastair E]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

Whatever mainboard you get-- It Must be one that drives the same make and model of LCD panel. TV vendor name is immaterial...

Vestel used all sorts of make panels including their own on later ones....

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

So how can I be sure? Do you know which no's to match. On the ebay listing most of line one of the white label matches but not the last 3 no's before it states 42", and the second line does not match!

And could it be fixed if I find the firmware to flash, do you know how to flash, I assume we use the usb?

Cheers.

[vinceroger69]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

ive had a quick look cant see one that matches the panel number maybe send this company a email and see what they say send them the tv make/model number and the panel number there a good company a few of us use them.

this is your lcd panel number not all sellers put this info on the adds
ves420undl-20-n03

this seller does list the lcd panel number used (just for refrence)
https://www.piese-servicelcd.ro/www-...420UNDL-2D-N03

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

So it cannot be worked out from the numbers on the mainboard? I'll message them. Cheers.

[vinceroger69]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

ignore wrong link

[vinceroger69]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

So it cannot be worked out from the numbers on the mainboard? I'll message them. Cheers.

im not sure if that white sticker has something too do with it?

[reessi]

Re: Hitachi 42hyt42u Turns off after 3sec - Vestal 17IPS71, 17MB95M

Thanks for your help, I will email a few of the sellers and see what they say. I will try and research about flashing as well, maybe someone else might see this thread and can advise.

Good night.