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Hello Everyone. Working on Proto 2 5 volt boards. Looking from those that have repair expierence. I have replaced mutiple Capicitors already that charge the battery or BCR. What im looking for now what are the other issues people are seeing? What else is failing? I have a few other boards that all the capicitors test fine on but they still are dead. Someone mentioned bad diodes. They seem to test good as well. I have attached pics of a board i have seperated and numbered. Keep in mind this is an older 5v board and does not have the extra capicitor. I have also numbered top board and bottom board. If you can, please refer to top board or bottom board with the number assigned in the discussion. I am determined to repair them and get them working again. Thanks for all your help!

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Images (4)
  • 20210207_084046: Top board 1
  • 20210207_085002: Underside top board
  • 20210207_084332: Top of bottom board
  • 20210207_084413: Underaide of bottom board
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Good luck.  There can processor failures, internal PCB trace failures, other microchip failures.  The heat used to separate the boards could damage traces and many of the SMD parts.

These boards are just beyond worth anything anymore.  Now if you enjoy beating your head against the wall, I applaud your effort, but working on PS-2 3V or PS-3 will be more worthy of your time.    G

@Paul Lytle posted:

...

I am determined to repair them and get them working again.

Do you have and know how to use an oscilloscope?

From what I can see, you did a nice job non-destructively separating the boards which is often the deal-breaker for guys attempting to mess with the PS2 5V board set.  But do you have a method to non-destructively remove the ~50 to ~100 pin surface-mounted digital IC chips of the complexity as found on the PCB?  When my eyesight was better, I used Chip-Quik for this purpose.

I see this as a matter of principle.  If looking at this from a business perspective - say from a tech who repairs train electronics for remuneration - then this is a no-win situation!  But if it is a personal mission in life to be the go-to-guy for what might be THOUSANDS of dead PS2 5V boards sitting in boxes (or the landfill), then hurray for you and let the games begin!  As I see it, the satisfaction of repairing something that has been written off as a lost cause is priceless.

There is some guy or guys on OGR that reverse engineered how sounds are stored in MTH PS2/3 engines.  This allows him/them to replace the stock sounds with whatever one wants.  I don't think any money changed hands and I've got to believe this was more than a weekend project!

One thing's for certain.  OGR is the right place to undertake the journey. 

@stan2004 posted:

Do you have and know how to use an oscilloscope?

From what I can see, you did a nice job non-destructively separating the boards which is often the deal-breaker for guys attempting to mess with the PS2 5V board set.  But do you have a method to non-destructively remove the ~50 to ~100 pin surface-mounted digital IC chips of the complexity as found on the PCB?  When my eyesight was better, I used Chip-Quik for this purpose.

Getting the boards apart is a major accomplishment, that allows you to get to many of the components that are otherwise out of reach.  For removing smaller chips, I've turned to my hot air tool, but the larger ones I'd have to invest in the nozzles specific to the chip, and I just don't have the call to do it enough to spent that money.

@GGG posted:

I think you will be held criminally liable when the head bashing starts trying to salvage 5V you provided.  G

You're probably right George, I'm calling my lawyer now to prepare my defense!

The problem I think is deeper.  There are parts that are obsolete on that board, let alone those with firmware loaded.  There are no design drawing out there. They are multi trace layer boards.  I have my process down to a science for 3V boards.  But still can't fix them all especially when the 5V and 3V buss is fused internal in the PCB.  Or the main processor looses a function from a short that is critical.  3V went obsolete for the same issues of specific chips no longer available.  Just compare it to a 3V and realize even if you fix one chip, another is about to fail on a 5V.  So unless your going to remove and replace all through hole and major SMD devices like diodes and FETs.  I think we had some one over a year ago going down this same road.  Never heard it was successful.

I am just saying pick some thing that the design was better to start and actually a desirable part.  It took me about a year and half to reverse engineer the 3V boards and fine how it worked, and it was a much simpler device. Then another year or so of finding common modes of failure.  We have no idea how the 5V fails.  We just know some are total dead, and other have direct shorts.  No real insight except the PV diodes, the rectifier, the swelling cap.  Audio amps, light fets and motor fets, no problem.  Everything else G

I finally got some time to dig into the boards. I started off with the boards that were causing an immediate short to the transformer when power was applied. There were 2 of them. Before separating the levels I removed the battery charge capacitor. I then removed the diode that covered where the pins were soldered into the board. After removed I was able to heat each pin and use my solder suction tool to remove all solder and loosen the boards. Note that the removal and connections on the board are very clean. Finally I was able to locate  failed diodes on the bottom side of the upper board. Before I go purchasing diodes. Any suggestion on the rating of the diodes and what would cause them to fail? 2 boards same exact issue.

Attachments

Images (5)
  • 20210225_113322
  • 20210225_113332
  • 20210225_115712
  • 20210225_115747 (1)
  • 20210225_120125
@Paul Lytle posted:

.... Finally I was able to locate  failed diodes on the bottom side of the upper board. Before I go purchasing diodes. Any suggestion on the rating of the diodes and what would cause them to fail? 2 boards same exact issue.

Can you mark in the photos exactly WHICH diodes failed (or did I miss it)?

And did they fail open or closed?  Note that if a power supply circuit, it's highly likely some of them are Schottky type.

Stan, I'm guessing the ones in the middle with the smutz on them are the failure items.   I notice in the other photos the discoloration of the bottom board where something blew.  The one diode in there seems to have different banding, so it's likely to be a different type.  Perhaps measuring some from boards that don't show failures will yield a guess as to diode type?  On a diode test on your meter, a Schottky should show a significantly different voltage drop.

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Images (1)
  • mceclip0

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