CurtPalme.com Home Theater Forum

jarseneau · Joined: 06 Nov 2007 Posts: 323 Location: WI

Anybody know if the 88 code is sometimes repairable?

Friday I picked up a local G90 and figured I had a really good deal since it was working at the sellers and all 3 tubes showed 0 wear. Had it home and was setting things up but after running for about an hour it kicked into an 88 code. I cycled power and the 88 went away but kicked back in within 5 minutes of running. I have my original G90 to borrow parts from and tried swapping the DALLAS chip on the YA board but still had the 88. So at this point I can run the 'new' G90 with the YA board from the 'original' G90 using the DALLAS eprom that has the setup for the 'new' G90 but it seems the 'new' YA board won't run. IC421 on the nonworking YA board has batch #003a01e which I know from other posts is the bad batch of IC421's.

So I'm kind of mystified as to why the 88 code suddenly materialized since the timer showed about 15000 hours. The CRT timers had the same last 4 digits as the total timer but from the tube wear it doesn't seem like the hours are for these tubes as there isn't even a 4:3 pattern on them.

Do these act intermittently at first and then finally go out? Is IC421 always the cause or can something else on the YA board (that is fixable) be the cause? Why would it be working at the sellers and then quickly develop for me?

I'm not too bummed about the purchase since I can use the tubes and other parts in my working PJ but definitely a shame to not be able to use the projector with the 88 code.

**Curt Palme** · Posted: Mon Nov 24, 2014 1:31 am Post subject:

Craig Rounds is the only guy that can fix this. Not cheap, but worth it. It's some other chip problem AFAIK, but don't expect Craig to give away his secrets. He won't even tell me. Smile

jarseneau · Joined: 06 Nov 2007 Posts: 323 Location: WI

I don't blame him for not sharing Smile

. I emailed Craig yesterday so hoping to hear Monday if there's hope.

hal · Joined: 28 Nov 2012 Posts: 100

I think that dallas chips are married to each YA board. When the Dallas chipset battery start to fail, you get the 88 code. I was getting on a intermittent basis. My recommendation is to buy a NEW Dallas chip and install it. Use the instructions on the internet which shows you how to reset the the chipset. Once I installed the new Dallas chipset all error codes stopped..

Edit: If the new Dallas chipset doesn't fix the error code, then you might need to send the board to Craig.

http://www.avsforum.com/forum/16-crt-projectors/1475508-vph-g90-88-error.html

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

A dead battery in the dallas chip causes a code 30. A red code 88 is hazardous to the machine. Tube damage can result in trying to use the projector with this code coming up. Do not use this projector (or the YA board) until it is repaired.

**Curt Palme** · Posted: Mon Nov 24, 2014 4:30 am Post subject:

What Mac said! The CPU is crashing, and I have seen spot burns caused by this error.

overclkr · Joined: 08 Mar 2006 Posts: 4227

CIR Engineering · Posted: Mon Nov 24, 2014 2:51 pm Post subject:

jarseneau · Joined: 06 Nov 2007 Posts: 323 Location: WI

CIR Engineering · Posted: Mon Nov 24, 2014 4:07 pm Post subject:

I don't think you need to waste time trying to diagnose this particular problem. The only thing that can cause an error 88 on a G90 YA board is for the computer system to be crashing. This problem is on the YA board and is not fixable by any simple means Sad

I don't think you did anything to cause this problem. Furthermore, error 88 can be fickle. By this I mean that sometimes you will get error 88 every time you plug in the G90. Other times however you may go months without getting another error 88. This is why the projector had no trouble at the seller's location. It's even possible that this is the first time the projector ever threw an 88.

I will say this though, once you get one error 88 you will get another and another and another. Eventually you will be watching the G90 when it throws an 88 and then your tubes will be ruined. Don't mess around with error 88 if your tubes are good!

craigr

CIR Engineering · Posted: Mon Nov 24, 2014 4:11 pm Post subject:

Email sent.

craigr

hal · Joined: 28 Nov 2012 Posts: 100

Craig, what are you charging to rebuild/fix the YA board?

CIR Engineering · Posted: Mon Nov 24, 2014 8:36 pm Post subject:

Hey Hal. It depends on the problem and the state of the YA board. Please email me with details and I can give you a quote.

Best regards,
craigr

Spanky Ham · Joined: 22 Mar 2006 Posts: 5643 Location: Comedy Central

Ummm, wait. Are you saying you can fix the YA boards or just certain problems on the YA boards?

**Curt Palme** · Posted: Tue Nov 25, 2014 6:13 am Post subject:

Everything but the IC421 issue of a shaking pix with eventual shutdown. Craig is DA MAN!

jarseneau · Joined: 06 Nov 2007 Posts: 323 Location: WI

Yes! Craig is DA MAN! Got my YA board back Thursday and no more 88 code. Everything looks great except something is off for the H-LIN RGB adjustment as I can't get the left side equal to the right. The range of adjustment looks similar to normal but even at MIN H-LIN, the right is just shy of correct. At MAX the right starts to curl instead of just compress. I've tried swapping the D boards located in the bottom of the PJ between the yokes but no change with that. I'm going to try the boards on the lid next but need to wait til I have more time.

CIR Engineering · Posted: Sat Dec 06, 2014 6:46 pm Post subject:

I just thought of this Jerry, because of the bending your describe. Did you center your image in the raster? If the image is too close to the edge of the raster the geometry functions won't work well or properly, especially on the right side of the screen.

Also, glad you are happy with the YA work. It was a pretty straight forward repair because your board dropped 88 errors frequently. The difficult boards are the ones that only throw 88's on their own every few months or so. That can be hard to track down.

craigr

jarseneau · Joined: 06 Nov 2007 Posts: 323 Location: WI

Today I swapped the E board on the lid and the H-LIN problem went away. When I put the original board back the problem was still gone. So I've since cleaned all connections for the 3 lid boards with de-oxit and that also got rid of some left side ringing bars when doing 1080p. I'm a pretty happy camper at this point.

CIR Engineering · Posted: Mon Dec 08, 2014 2:24 pm Post subject:

Excellent!

I would take a hard look at all the solder joints on the E board. You can see the underside of the E board without taking it out of the projector. Just remove the plate on the projector lid that is over the E board and have a look with a magnifying glass and bright light. Also note that the cover plate has three holes in it for you to be able to pass an allen wrench through. You can use those to adjust the width coils if you are adventurous.

craigr

jarseneau · Joined: 06 Nov 2007 Posts: 323 Location: WI