LA chip or laser?

[modicullus]

I just got an email yesterday from a customer who's v9 PS2 I did about 3 months ago saying 'In the browser it'll just flash "reading disc..." continually.' That's my first v9 with any problems! He's supposed to bring it in to me to take a look at it tonight, but I'm not sure how I can tell whether it's a problem with the LA chip or with the laser itself. I've read through the 50,000 posts regarding the LA chip now, but haven't been able to find any definite answers. Someone might have to create a 'summary' of what's been found/speculated on the LA chip to date.

Should I measure the resistance on the tracking and focus coils like in the attached picture? If the resistance is below 5ohms, does that tell me that both the laser and LA chip or toast. Actually, is there a method to determine whether the LA chip is still good (like the pin 8 test on the BA chips)?

Anyway, if anyone can suggest a few things to help me out, that'd be great!

Cheers!
m

[modicullus]

Sorry,... one other thing...

In this attached picture (adding the resistors for the tracking and focusing coils) - isn't this for preventing the LA chip from blowing?

Thanks again...

[LanEvoVII]

i changed laser and solved everything

[modicullus]

Okay,... the fella dropped off his PS2 and I had a chance to take a look to see what's going on. Upon inspection I found that the problem was that the spindle doesn't spin and the laser doesn't track back and forth. You can see the laser beam (or whatever) and it focuses up/down. It's a HD7 laser btw.

I ripped the machine completely apart and measured the resistance on the coils (like in the first attached picture above) and here's what I got:

Tracking Coil: 1.8 ohm
Focusing Coil: 5.4 ohm

I also took the cover off of the laser and took a look at the actual coils, and they appear to have overheated a bit. It looks as though there's some small bubbles on the coils. But nothing too serious.

Now I assume the reason the laser doesn't track is because of the low resistance on the tracking coil. Now here's the questions...

First off, how the heck can I tell if the LA chip has been damaged? Or if the laser unit can still be used? If I simply add the resistors like in the second attached picture above, will this allow the laser to track (I doubt it, but I had to ask...)?

And my final question... what the hell should I do??? Do you guys think I should try replacing the LA chip and throw a couple of resistors in like in the above attached picture? Or should I try another laser altogether? (btw - I don't have an extra v9 laser or an LA chip - I'll have to buy one... which brings me to yet another question... can someone suggest a good place to get these?)

Sorry for all the questions, but this is the first time I've had to deal with the v9/v10 syndrome, as I had previously thought it was pretty much isolated to PAL machines. Oh yeah... this is an NTSC machine btw.

Thanks,... and any help or suggestions would be greatly appreciated!

[Gladiator]

That sounds like a burnt LA chip. Whats worst is that you say the spindle does not work either, so that means the LA is probably gone totally.

You may want to replace it, buy a new LA or buy one of the clones(the one that totally substitutes the LA).

We are working on the schematics of a total LA replacement, but nothing final yet.

You can also try the partial LA replacement with a BA see if it works(though I doubt it since the spindle dont work).

You can see the schematics here:

http://www.ps2newz.net/forums/attach...?postid=142880

Say thanks to Kaiser for the schematic.

[modicullus]

Thanks a mil for the reply Gladiator. I've been reading all of the posts on the LA chip and I'm glad to see that you guys are close to a BA solution for the LA chip.

Do you know of a place where I could find a new LA chip? I think I'll replace that for now and see what happens. Also, do you think that the laser is probably still ok? I'd hate to have to tell the guy that both of them need to be replaced!

When I replace the LA chip, I'll add the resistors on the coils. Hopefully this will be enough to keep the PS2 running for awhile. Whadda figure?

*EDIT*
Found this link fro EnTiTy in another thread for LA chips:
http://www.darkplanets.com/products.asp?id=169