Fixing my G90.. - Page 3

John,

There is some contention about that technical bulletin being a hoax.

Talking "technical bulletins"...is there a source for these for the G series? I tried a search of the URL in the link...but no joy...also Sonys FTP site requires a password....can somebody point me in the direction of?

I would like to know this also. I know that someone here must have these bulletins, and I'm surprised they haven't surfaced yet.

Sony wants something like $4K for their technical "library".

I seriously doubt it's a hoax. Especially since Sony has had blank PC boards on their parts list since I can remember.

Though this particular board does have some parts missing, it looks better than some of the ones I've received after thinking I would get a complete board from their parts depot.

That problem is ES (electro-static - cause, external to PJ..) damage. I knew that when there was an open SMD resistor that was not broken. Plus, everything posted on this problem indicates it.

I have a G90 service manual somewhere on a CD. I'll see if I can find it, and see what I can add here.

I've had problems many times like this, and my approach was to always pull-up the data lines and look for resistive shorts either on the chip, or the ESD protect device before the chip. But in the case, the ESD protection seems to be in the chip itself, and in most ES damage devices, the load can be detected with an ohm meter by pulling the data lines and testing for leaks right at the chips data feed.

Also, that same DAC controller chip may have another part number, and may not even be made by Sony. So it's possible that the chip is still around, but with another part number on it.

Thx for the idea Ed but I already checked this and the G70 do not use this device but rather multiple separates CPU to provide multiple I²C buses.

Axatax : the technical bulletin is surely NOT a hoax, I've found it from www.sonysupport.com official Website by typing the "VPH-G90" sentence in their model search engine. Then I've got "REUSE ICS WHEN REPLACING YA BOARD 302006088 19/06/2006" link on the list. The issued date of this TB is just 8 months old


I doubt Mike : this device seem's to be a pure Sony designed specific IC (and probably only for G90 projector). Also agree with you about ESD failure(s) on this unit but according to SM, the only part between IC421 and output connector is IC13 (TC74HCT541AF). This leave IC421 itself...

All : I still not have any feedback from UED.net about CXD305 device. I can order it and put it in my shopping cart. but at the end of the process I get "Sorry, international orders cannot be proccessed on the website at this time" for an unknown reason (tried three times)... Can someone from US try to proceed shopping this part and see if he can order it or not ? Thx

John

John:
According to the UED web page - the item (number 875239188) is not stocked. E.

True Ed, but according to https://www.ued.net/ued/addItems.do?...e=SNY875239188 , the "The projected shipping date of this item is 03/01/07."

So this means that they have to order it from another supplier (Sony).

John

Umm......what planet have you been on???? Sony G series have always been the hardest to get parts for. I'm tripping over NEC parts - I'm giving half of them away to one of the other Aussie CRT guys.

OK, John:
I have ordered the part for 95$. If and when it arrives, I will send it to you. Let's hope that SONY has some squirreled away somewheres! BEst - Ed.

Thanks Ed, that's kind of you

I really appreciate but unfortunaly I've just received one answer from Harry Benson @ued.net and he wrote :
I checked with Sony and this part is discontinued unfortunately. Sorry I couldn't help.

I'm affraid you'll get the same answer after your order. We'll see.

I'm condamned to buy a brand new YA board or maybe a defective one (to recover IC421) if I could find such board around here

Any idea of a brand new YA board price in USA ? Here is France it's $2416

John

John there is a G90 for sale "buy it now" on fleabay with TOASTY tubes, maybe a few of you should get together and chop it up for a parts machine....

Okay,

Here is the summary of the 'ex' Curt's G90 unit after finishing servicing the unit :

- Found BA board Green Bias issue : R603 (100K 0.5% SMD0805) : found it opened. Resistor replaced : Solve the Green BKG CONTROL issue. Cost : free. Time = 3 hours.
- Ya board I²C buses issue : found DACs controler IC421 (Sony CXD305-127R) that should be defective. Hardly tried to find a replacement part on the net : no more available. Send the board to Ed. (glassact <- Big thanks ) to let him resend it to Sony repair sevice center at San Jose. Board fixed by Sony (IC421 and IC431 were replaced with part that came from Sony Japan). Total YA servicing cost : $1813 including Shippings No choice .Time = 15 hours.
- Found another BA board issue on B/C RGB inputs : Green channel grayscale is compressed after 60 IRE (non-linear). Issue located on IC2 MAX4121CSA (2:1 300MHz MUX). IC2 replaced -> issue solved. Cost : $5 . Time = 2 hours.
- Found EA board issue on H-KEY and H-PIN adjustments (that made nothing on the screen). Issue located on IC2 MC1495BP (four quadrant multiplier) which has pins 8/9/10/11 wih low impedance shorts. IC2 replaced -> issue solved. Cost : $5. Time = 2 hours.

As curt's feeling, this unit should been striked with lightning on Main as the failures I found are relevant to such effects on electronic chips...

Fortunatly, I could swapp the board with my first unit to ease the location of the failures .

I've fully retubed the unit (thanks to Chuchuf for the Red, thanks to Fireball66 for the Blue and thanks to Greg Eisemann for the bare green P19LUG HR)

Changed Green 'C' Element with Marquee one for green color purity (thanks to Tim).

Added one IFB-DVI-V2 card in B slot.

I've spent 2 hours on adjusting D65 grayscale tracking with Spyder2Pro and Colorfact 6 Pro.

The unit was sold and installed yesterday : picture is stunning on 2.7m wide screen with HD-DVD from Toshiba HD-XE1

Total cost for servicing the unit : 8500 - Sold: 6500 : this was not a good deal but it helps me to teach the complete electronic of the G90 : now I'm skilled in it

Cur't you've been cleaver enough to sold this unit to me it was holding a lot of differents electronic failures The YA board one was the most costly one; unfortunatly for me

John

A financial loss, but a technical victory. It's great that you got it working again at all. Sony's policies are frustrating, but at least they have not yet stopped servicing the G90 altogether, as I originally thought.

-Mark

WOW!

Nice work John. It's really hard to fix a unit when there are so many different issues. I always find myself second guessing if I'm missing something. Like you say, now you are an expert though

I used to own a business repairing Pinball (flipper) machines. I'd buy trashed ones at auction and rebuild them. Only choice was board level repair. Usually most units had dozens of bad ICs... The challenge was always the fun part.

craigr

Hey Craig! You need to change you location in your profile now that you have you new place !

Athansios

PS Check out some screen shot i posted of the mArquee you calibrated scroll down a bit.

http://www.avsforum.com/avs-vb/showt...=784331&page=2

Congrats!

Very good work John!


Sounds nearly like a never ending story. I am glad for the happy end...

Axel

ERROR 66 on G-90

Have a G90 that suddenly developed a problem. Used it one night inputting 1080i off cable. Image was gorgeous. Trouble free. Next morning, the projector was screwed. Without input signal in its warm up cycle, I could see low res scan lines. Warm up post was shaky and distorted like there was some kind of internal oscillating problem. Switched projector off and on but no correction. Menu also had a similarly messed up image. At first there was no error message at all. Gradually, after a few attempted start ups I got an Error 66 reading. The manual indicates that the most possible problem is in the E Board, related to horizontal deflection (H. OUT). Having problems tracking down this board. It's part number A1346772A. Anyone know where I can get one? Anyone know if the G-70 projectors use a similar board? Any caveats on replacing the E Board in this projector?

Occasionally the projector can boot normally and output a steady signal in its current state. However, as soon as I cut the input signal the image destabilizes again. Or, if I press something on the remote a steady signal might suddenly destabilize. Now, when I press the menu key in the warmup cycle the screen goes blank. I'm not even seeing error messages on the led diagnostic anymore.

Don't know what first caused this problem but my guess is an electrical surge through the cable box to the projector. I didn't have the cable on a surge protector and I noticed the cable box was a bit disoriented too. I had to reboot the cable box to get it back to normal. This clued me in on the possible cause. Belatedly, I have the cable on a surge protector.

Posting two images here to demonstrate what the boot looks like.

Looks like a H-sync problem to me. I'm no Sony expert though.

I would that that any H-def problem would make it shut down completely.

Well, that's what the E board addresses. Here's what the G-90 manual says (referring to the "66" ERROR protector code),

"This protect works when the horizontal deflection is inactivated. The most possible failure is H.OUT of E board. If not, failures might be found in H. Drive series or the negative power source series. Look into DA/EA/ED/PD board."

I don't want to make it seem that all problems stem from the SVRAM chip - but it may be the problem. When the SVRAM chip runs out of on-board power, error codes abound - none of which are caused by defective boards. I have had d5 errors, 39 errors, 86 errors, and others come up - as well as bad images similar to yours. It seems that the SVRAM chip controls the electronic convergence functions of the G90 - and when the chip goes, the electronics go off scale, leading to numerous unrelated problems.
Worth considering, particularly as the problem suddenly occurred. Best - Ed

Good point Ed,

Had the same kind erratic errors displayed on the G90 two digits display when the YA board had the I²C buses communication issues (bad data sended). If the NVSRAM chip content is damaged, the data sended to the DACs cards are corrupted and generate numerous errors that are not relevant to their cards but rather to YA ...

John

John and Ed,

Both of you have noted problems peculiar to the G-90 and its SVRAM chip which gives false error signals in the boot protector circuit.

If this is the true issue here and not the board, how is this corrected? Is the SVRAM chip replaced or reprogrammed? Do you have a part number on that?

Thanks,

Howard

http://www.avsforum.com/avs-vb/showthread.php?t=841021

On G90, NVSRAM chip reference is DS1245Y-120 but you can use -90 or lower access time as well.

But based on your pictures, it seem's that the horizontal deflection board have a failure that NVSRAM content can't generate in your case...

John

John,
I have a G90 with an orange 89 error code. I swapped the EBH board per the manual with no success. I then swapped the DC board incase I was reading it upside down. This also had no success. I tried the YA board and it fired right up. Where did you send your YA for repair?
James

PS The IFB-DVI you sent me is awesome, thanks!

Don't let Cliff or Clarence see this!!

wallace

I had the orange 89 error with the bad SVRAM chip.
Look, folks - this is getting a bit silly. The chip has a maximum lifespan of 10 years. They cost 45$ to replace. Before you send the machine or board to SONY - make sure it is not the chip.
Once the chip starts to go - all bets are off. The pj goes out of spec and things begin to show up on the error chip. That seems to be the nature of the machine. Even if the chip is not the problem - it needs to be replaced if the g90 is over 8 years old. So says I.
Best - Ed

Which reminds me Ed - did you get the $45 from Adel? I asked him to send it and forwarded your details.

Mark