When your games go on the fritz - Suteneko's repair & mod thread.

Suteneko · December 24, 2020, 5:15pm

Thought I’d start up a repair log thread where we can compile the various repair work we’ve done for when those Gremlins throw a spanner into the works. Hopefully the repairs logged can prove useful in assisting others when they run into similar problems and I hope others will contribute.

Suteneko · August 4, 2018, 1:01pm

Donkey Kong Country 2 - SNES Cartridge Repair

I received a Donkey Kong Country 2 NTSC/U cart as part of a SNES cart lot I purchased this morning very cheaply. Unfortunately upon testing the cartridge I found that it refused to work.

I expected it would just be a simple use a rubber to clean the contacts fix. However, after opening up the cartridge I found that there is a crack all the way through the game PCB along several of the edge connector pins:

Using my multi-meter I confirmed that there were broken connections on 5 of the front “parts” side of the PCB and 3 on the rear “solder” side of the PCB.

First to re-enforce the PCB so the crack could not get worse through regular plugging and unplugging, I used small dabs of super (Gorilla) glue on top of the cracks between the pins on both sides and then ran a small amount of glue down the side of the connector.

Once this was dry I added some solder to the damaged pins which was lightly dragged across the pins to repair the broken connections. These were then tested with the multi-meter again to confirm the connections were solid. While quite unnecessary, I also applied a very light amount of solder to the two pins to the side of the repaired ones just to help give the connector a little bit of extra solidity against the crack.

As usual I then just used a rubber to clean up the connector and replaced the CR2032 tabbed battery with a brand new one. For those curious the old one was reading a little low at 2.9v.

I then re-assembled the cartridge, placed it into my SNES and turned it on:

poptart · August 4, 2018, 2:38pm

Nice idea for a thread. I have a GBC game and a couple GBA games that do not boot. They don’t even get the Nintendo logo showing up. I can’t figure out what’s wrong with them but thanfully they were all cheap.

Suteneko · August 28, 2018, 10:17pm

Chrono Trigger - SNES Cartridge Repair

I recently saw a Chrono Trigger listed as non-working, spares and repairs.
The seller also provided an image of the cartridge showing a damaged connector shown below:

Everything pointed to the cartridge being legitimate but the the original asking price was too high for me to gamble on a possible repair. However, after contacting the seller directly we came to a reasonable price for me to take the risk of attempting to revive the cartridge.

A couple of days later I collect it from my local post office and get to check it out for myself:

Good news is that it is indeed an original legitimate cartridge and all the chips appear intact.

However the cartridge connector as expected is heavily damaged and unfortunately there is also damage to several traces above the connector on the PCB:

I attempted to straighten the connector and then bridge all the breaks along all the pins on the cartridge connector with solder but even after doing that that it still felt too fragile and would require a fair amount of rewiring to fix the additional broken traces.

@khaz gave the great suggestion of:

Break it clean, glue it with epoxy, then repair the traces with some solder

However while this may have been stronger it would still require a messy internal rewire and with the damage going above the connector breaking it off would likely cause more damage to the PCB.

So I decided to instead remove all the chips from the game PCB to prepare for a transplant onto an identical donor PCB from a cheap Super Famicom game.

The removal of them was successful and painless. I would advise anyone attempting to do the same to add a little bit of new leaded solder to all the solder joints prior to using a solder sucker as it makes everything easier and the result much cleaner.

ROM: Chrono Trigger (NTSC/U)
CIC: D411B (USA)
Memory Mapper: MAD-1
SRAM: 64k

So now I needed to find a cheap donor game with an identical SHVC-1J3M-20 PCB.

I used Snes Central which is a great resource for SNES PCB scans and found out that the following games would be suitable:

I opted to go for a Japanese Chrono Trigger:

But unfortunately I ended up with an undocumented 2 ROM SHVC-BJ3M-20 version of the PCB:

So now knowing it would be a lottery trying to purchase another Japanese Super Famicom Chrono Trigger, I instead opted to do a little bit more research and I ended up getting a Dragon Quest VI cartridge which indeed had the identical SHVC-1J3M-20 I was after:

I initially only de-soldered the ROM and MAD-1 A chips from the Dragon Quest VI cartridge and replaced them with the Chrono Trigger NTSC/U and MAD-1 chips which was the bare minimum I was required to be able to test if they worked (they did), but I then also replaced the CIC and SRAM with the original ones from the Chrono Trigger cartridge as well for the sake of authenticity.

Due to there being a half size 64k SRAM on the Dragon Quest VI donor board I had to also clear the solder from the top row of pin holes to be able to insert the original full sized SRAM chip from Chrono Trigger:

Then I bridged the left over and soon to be unused through holes as they were on the original PCB:

I then proceeded to finish up the transplant and replaced the battery with a brand new Panasonic tabbed CR2032 battery giving me the final result:

Time to re-test it on my SNES and an hour or so of playtime later:

Chrono_Trigger_w

I am very happy with the result!

Just for those curious I have not thrown away any of the Dragon Quest VI chips or its case for that matter. For now they have been stored away in my parts box. Having a known working CIC and 64K SRAM could prove very useful for future repairs.

raskulous · August 29, 2018, 1:47am

Very cool, nice work!

Peltz · August 29, 2018, 10:39am

https://media.giphy.com/media/Fkmgse8OMKn9C/giphy.gif

Impressive work!

Suteneko · May 2, 2019, 1:56pm

I recently picked up a NTSC-U version of Final Fantasy II that was listed online cheaply because the game wouldn’t save which is a fairly easy fix so I picked it up!

Indeed it is not saving, but anytime I get a new cartridge in that has a battery backup I open it up and replace the tabbed CR2032 anyway. So no big deal and lets open her up:

Everything looks legitimate so time to remove the battery which came out very easily (take note of this):

And now battery replaced with a brand new Panasonic tabbed CR2032 battery:

The battery should be capable of holding a game save in SRAM as long as its voltage hasn’t dipped below 2.8v and a brand new battery should measure around 3.2 to 3.3v.

So out of curiosity lets check the old batteries voltage:

WAIT!!! WHAT??? Why is the old battery measuring 3.353v?
That is like new and shouldn’t be having any issues!

So the way the battery backup saves work is that the Memory Mapper chip has an additional function built in that detects voltages on your cartridge. When there is a drop of voltage below 5v it switches the SRAM into a low power state and starts to supply it with 3v from the CR2032 battery to the CE1 (chip enable) pin. When the cartridge regains power again from your console the 3v supply from the CR2032 is suspended and the SRAM is powered normally via its VCC (power input) pin at 5v.

I made a simple diagram below:

From this it is easy to diagnose any additional problems by following the steps below:

Check for 3v at the MAD-1 Input pin. (Check for broken trace from the battery if 3v is not present)
Check for 3v at the MAD-1 Output pin. (Replace the MAD-1 IC if 3v is not present)
Check for 3v at the SRAM CE1 input. (Check for broken trace from the MAD-1 if 3v is not present)
Check for 3v at the SRAM VCC input. (Replace the SRAM IC if 3v is not present)

After testing it looks like everything is working as it should:

This leads me to believe that either a previous owner attempted to change the battery but didn’t do a good enough job of soldering in the new tabbed battery or that a solder joint on the battery was cracked from a drop of some sort.

I didn’t think to check the batteries connection in advance and simply removed it as usually these batteries tend to be near end of life already.

So I re-assembled the cartridge and made a save, turned off the power, then many hours later turned back on my Super Nintendo and my save file was still there:

SUCCESS!

Hopefully the extra unnecessary information for this repair will help others.

fester · May 1, 2019, 12:16am

I’ve only had one cart that needed repair (Game Boy Metroid II) and unfortunately wasn’t able to bring it back to life, but this has given me a bunch of ideas for things down the road. Thanks!

Suteneko · May 1, 2019, 12:19am

It is a shame you can not find datasheets for the custom Nintendo Memory Mappers, but fortunately it is quite easy to find them for the SRAM chips so you can work backwards from the CE1/2 and VCC pins to figure out where voltages should be going.

Peagles · May 1, 2019, 2:19am

(This is awesome stuff, you’re so clever)

Suteneko · May 3, 2019, 11:07am

I had been interested in picking up Blue’s Journey for my Neo-Geo MVS, however the going price online was a bit too high for my liking. So when I saw a cartridge listed as non-functioning for spares and repairs, I sent over an offer I was happy to risk the chance of not being able to repair it and purchased it as a project.

When the cart arrived I tested it in both my MVS and it would not boot at all.

So I opened up the cartridge to take a look at both the PCB inside:

Nothing looked out of the ordinary apart from the cartridge connector pins being very dirty, so I cleaned them and had to resort to using a Fibreglass Abrasive Cleaning Pencil to remove some corrosion that had started to appear on a few pins.

The MVS cartridge however would still not boot so a closer inspection was required and I found a broken burnt out trace on the rear side of the PROG8M42 (Program) Board:

This was easily repaired by soldering a jumper wire from the cartridge pin to the via:

Unfortunately the Blue’s Journey MVS cartridge would still not boot.

From researching online it became apparent that the reason a lot of MVS carts would not boot was because of a bad program Mask ROM and the only way for me to really test it was to remove it:

Now I needed to figure out a way to read the Mask Rom and for this I needed to find the Eprom equivalent which had the exact same pin out.

The program was situated at the P1 location with a silkscreen marking of HN62408P and the Mask Rom is a TC538200P which is a 42pin 8Mbit (1MB/1024KB) 512Kb Word x 16-Bit/1Mb Word x 8-Bit IC. After searching datasheets for 8Mbit eproms I found that a M27C800 was pin compatible:

MVS_BJ_Repair07

So I set my TOP3000 Universal Programmer to IC M27C800 and attempt to read the contents of the P1 Mask ROM and I get an error. Pin 28 (D14) will not read:

: MVS_BJ_Repair08

This proves that the P1 Mark ROM is faulty. So using the 022-p1.p1 file from out of Mame’s Blue’s Journey ROM (bjourney.zip) I program a M27C800 eprom and solder it into the P1 position on the PCB as a replacement for this fault mask rom:

So let us test it again:

IT BOOTS UP and WORKS! But wait a moment, notice anything? Something is still wrong…

There is sound but some graphics are corrupt:

Before I continue I should explain which ROMS on a MVS cart do what:

Px ROM: Program Data
Vx ROM: Audio Data
M1 ROM: Sound Program
S1 ROM: Static element Data (such as Fonts and UI elements)
Cx ROM: Graphics Data

Because we have good sound and the game is running now, we know that the only ROMS left that could be problematic are the S1 and C1-C4 Mask Roms.

However, all static elements appear to display correctly as you can read the fonts and the High Score screen displays perfectly in its current state:

So we know that it is unlikely there is any problems with the S1 ROM which just leaves us with 4 Graphics Data Roms to check. However it is not possible to check them in circuit so they need to be de-soldered:

Both C1 and C2 are 8Mbit 42pin TC538200P Mask Roms however C3 and C4 are 4Mbit 40pin TC534200P Mask Roms and my programmer doesn’t support them.

Since they are also marked on the silkscreen as HN62408P they should also be pin compatible with a M27C800 eprom and after confirming with the datasheet they do indeed match.

The only caveat being that when I read the 4Mbit Mask ROM as a M27C800 I need to ignore the pin “1” can’t be read error as it doesn’t exist and I get a doubled up 8Mbit file which needs to be split into two 4Mbit chunks by a program such as BINman to be able to compare its CRC with a known good one.

So I read and dump the contents of the 4 Graphic Mask ROMS and find that C4 will not read pin 29 (D15) :

MVS_BJ_Repair14

So I now know that C4 is faulty.

I then extracted all the relevant files out of MAME’s Blue’s Journey ROM to compare them with my dumps to confirm they are all good and they all match!

I can now solder back in the mask ROM for C1 to C3 knowing that they are good:

You can test MVS cartridges with missing Graphic ROMS without any issues. The only thing that will happen is that you will have missing graphic tiles and layers from the detached Rom which can be utilised to try to figure out which roms are faulty.

In my case the very last rom I removed (C4) was the one that removed the faulty graphics. It also can look quite funky seeing the game running with missing tiles as tested below with only C1-C3 soldered in:

Since I had no AM27C400 eproms at hand that are pin compatible with the C4 TC534200P mask ROM I instead used another M27C800 eprom to replace the faulty C4.

To do this I extracted the “022-c4.c4” file from out of the Blue’s Journey Mame ROM and then made a copy of it which I then opened in HxDen and then zero filled the entire 4Mbit (512Kb) file and saved this as “4Mbit_Blank.bin” . Then in BINman I merged the two 4Mbit files together to create a 8Mbit file:

MVS_BJ_Repair17

I now programmed the resulting file to a M27C800 eprom and then soldered it into the C4 IC position:

Now time to test it again:

SUCCESS!

NOTE:

While this sort of repair can fix a lot of MVS carts certain games use 64Mbit Mask Rom’s (such as Strikers 1945 Plus) and eprom’s only go up to 32Mbit in size.

This took way too long to write up! Hope you enjoyed the read.

DaveLong · May 2, 2019, 6:38pm

That’s a fascinating writeup! Thanks! My old Comp Sci degree let me understand that sorta, but wow… I’m just really impressed that this is possible to revive a cart like that. I have a Super Sidekicks 2 that I should send you! lol!

Suteneko · May 3, 2019, 11:23am

Blue’s Journey has one of the more simpler board layouts for a MVS game.

There are plenty of custom IC in other MVS games that can cause issues and these can not easily be replaced unless you use a donor from another functioning cartridge.

Luckily sometimes the custom IC just needs its solder re-flowing.

My Shock Trooper MVS cartridge arrived a while back with non functioning sound, which was fixed by using hot air to re-flow the solder around the custom PCM IC while pressing it back down into place.

It must have suffered some bad shocks (excuse the pun) during its delivery to me that broke some of the connections to that IC.

DaveLong · May 3, 2019, 2:22pm

Cool. Thanks for all the info! I am definitely going to open up the Super Sidekicks 2 and have a look around inside. I received it with some other Neo Geo games awhile back and the guy told me it doesn’t work, which of course it does not. It’s worth a peek after reading your repair job to just see if I can at least identify what might be the problem.

Shinriji · May 3, 2019, 4:53pm

Amazing. Is there a video for some basic soldering lessons? I’d love to fix some of my stuff that requires soldering, like my saturn controllers.

Suteneko · May 3, 2019, 10:49pm

I am self taught and my initial attempts were terrible if not disasterous on a few occasions. Getting the right equipment from the start is probably more important as the cheap soldering irons and solder will make things difficult before you even start.

Go for some mid range temperature controlled soldering Iron, get some no clean flux and some 60/40 leaded solder and then just buy some cheap electronics kit (or find some old electronics pcb you do not care about) and just practice until you find what works for you.

I may have my next project lined up for this thread already. Possibly Capcom related but we shall see.

Addicted · May 8, 2019, 5:57pm

I’ve been working on a couple Goodwill finds.

This poor DMC. I had to heat up the ribbon cable to get rid of the vertical lines and give the plastics a bath followed by a little isopropyl alcohol with a toothbrush.

360 Controller:

Spilled soda: Yes Battery Leakage: Yes Owner tried to fix with duct tape and a screwdriver: Yes

I’m taking it apart now and giving the plastics a good isopropyl alcohol scrub with a toothbrush.

Addicted · May 14, 2019, 12:41pm

So I took apart the controller and gave it a good cleaning. Thankfully no leaking on anything besides the battery compartment.I might buy replacement thumbstick caps as one is a little loose but not enough to be a big issue.

The GameBoy plastics cleaned nicely with water and dish soap. I was able to use my soldering iron to bring back the display.

I have a Sega CD Model 2 that I recently repaired I’ll post pictures of later.

Addicted · May 28, 2019, 12:34pm

So I recently picked up some Duke controllers from a local Goodwill.

One worked but had a frayed cord (a common issue). The other one didn’t work at all and looked like the cord had worn enough that a wire snapped.

I cut the cord and stripped it at both ends so I could solder the wires together. I then wrapped each wire up in electrical tape and then taped them all together. The controller works great now even if the length of the cord is a little shorter.

Suteneko · May 28, 2019, 1:42pm

I’ve repaired some official controllers with damaged cords before and have realized that I prefer to just get hold of some cheap unofficial third party tat pads that no one wants which also have good cords and transplant them over as even with heat shrink the results just don’t feel satisfactory to me and well transplanting over a cable is much less fiddly to do!

Sometime cheap extension cables can also work out quite well.

But anyway: Good Job @Addicted