SNES Repair Help - Carts Won't Go Beyond License Screen

Hello everyone,

I was referred here from Racketboy and am hoping someone can help me with a SNES issue. Please forgive me if I'm doing anything wrong with this first post -- I'm totally new to your forum and don't know how you guys roll yet.

THE ISSUE: Our SNES (original model) has gone on the fritz. Carts work fine, but they don't go past the preliminary screen. For example, with Mario Kart and Mario World, the Nintendo logo comes up, but never progresses further. For SimCity, we get the opening splash screen and music, but can't advance beyond that.

I've cleaned the carts with alcohol and electronics cleaner, and did the same with the console as much as I could without opening it up (dipping the hem of a soft shirt in alcohol and using a credit card nestled within to get between the pins, then later spraying a bit of electronics cleaner in there and doing the same credit card trick). Nothing changed.

The system has never had an issue before; I was using it only weeks before our most recent move, same as always. My suspicion is that it got jostled around in transit and maybe something came loose inside... but that's just a guess.

I don't currently have the tools to open up the console and look around, but when I do acquire them, does anyone have an idea what the problem might be, or how I could fix it? Any thoughts would be appreciated. Thank you so much.

 

Welcome to Assemblergames!
The sound plays further after the screen freeze? I would open the console and check if there is mod or something loose.

 

These consoles are strong ,my friend tripped on the controller cable and the console fell 4ft on a hard floor and the game crashed. The console works fine.
I would put a game in and out of the console a good few times with it turned off . It cleans the connectors.

 

Could be the CPU died

 

What you need is a test cartridge. It will tell you exactly what is broken.

 

You could always open it and look to see if anything got physically damaged but as Tokimemofan mentioned your CPU could have failed or some other component. The SNES is somewhat notorious for CPU failures that don't result in a totally dead system. Various parts can fail causing partial operation depending on the program running. One of the official SNES test cartridge programs can give some insight if this is the problem. It's also possible the WorkRAM could be dead. Or maybe you have a bad solder joint or cracked trace on the board. Unfortunately lots of things could be why you are having problems. When cleaning the connector and carts doesn't fix it you have to start getting into all those other things.

 

Wow guys, thanks for all the information. I did get the proper bits to open the console, and earlier this evening I disassembled it, air jetted, cleaned contacts again, etcetera. No change. It's pretty dang clean in there.

But, a friend of mine gave me her long-unused SNES to try, knowing that mine was having troubles, and with that I was able to at least confirm that it isn't the APU that's having problems. After I got her console cleaned and functional, swapping our APUs resulted in her SNES working fine (meaning my APU isn't dead) and my console continuing to have the same problems (meaning it's something else on the board).

I'm going to continue digging deeper into fixing my SNES, because it's important to me. But at least I have a working console to continue playing games on my to-do list this summer.

How does one go about getting a test cartridge, by the way?

If anyone has more tips, I'll always be grateful to hear them. Thanks again, all.

 

Was it your original SNES? Just recently my original SNES unit has suffered a sudden failure too. I've had it since the early to mid-90s and got it brand new. I had played it no more than a month earlier and everything was fine. I went to play a game and noticed glitched text. I thought it was the cartridge but then when I went to try other games after cleaning did nothing to help, I noticed all games had graphical issues. What has happened to my system is likely an internal failure inside one of the two PPU chips. From what I've been told it's not really a great idea to attempt to remove and replace the PPU chips with pulled chips from another system since the problem could be either of the two chips and the heat exposure on the components during desoldering and soldering can cause failures too.

So what I did was obtained another unit, swapped the PCBs between my original and this other unit. So my original console shell has a fully working board in it, while the original PCB with defective PPU chip is in the other lesser condition case. I'd like to be able to repair my original console's pcb but it's not so easy or without risk. Unfortunately it seems like the SNES is somewhat notorious for failing components.

You could get a flash cartridge from infiniteneslives.com and program the test cartridge ROM onto it. Other places might sell test carts using EPROMs or you could possibly run the ROM from a flash cartridge like PowerPAK or EverDrive, but it may not be possible to load the ROM on a partially functioning console, so it's better to use a cartridge that just contains the test program.

 

hi key , i'm glad the members here are helping you out. I referred you from Racketboy forums , you may want to try Deoxit Red and Gold. You apply it to Console Slot contacts and Cartridge games , Red cleans really well and Gold seals the surface. I actually pulled my Neo Geo AES today and was getting no audio and glitchy GFX. The MVS to AES converter i use was dirty so i used Deoxit and now it's working again. It may be as simple as that , contacts need better cleaning than Isopropyl can provide.

 

i thought of another thing to try , when your SNES is on are any of the chips/processors really hot to touch ?

 

Most common faults on 1st gen SNES are the CPU, PPU1, S-WRAM and PPU2 in that order.

PPU faults usually don't prevent the unit from booting but cause graphics or game logic glitches. CPU or S-WRAM chips fault make the unit unable to boot.

Broken traces are also common to a extent (the motherboard is of high quality and is very unlikely to fail this way).