Super castlevania IV cart has stopped working

The cart has suddenly stopped working, I just get a black screen when I turn on game. All of my other games work so it's not the console. I've thoroughly cleaned the contacts but all I get is a black screen. Any ideas on anything else I can try to bring it back to life?

 

Super Castlevania IV uses a very simple PCB. It basically has the Mask Rom which contains the game binary, a CIC or "Lockout Chip", a few resistors and an electrolytic capacitor. The first thing that I would do is look at the capacitor and see if it has leaked or is bulging. If you see that it did leak fluid on the PCB, remove the capacitor by clipping the leads with a wire cutter and clean the leaked fluid IMMEDIATELY as this can do serious damage to the board. Use isopropyl alcohol (90% or higher only) and a q-tip and get all of it off. If you still have some stubborn gunk, you can try a SOFT bristle toothbrush. You really wanna try as hard as possible to not damage any of the traces when cleaning this up. If you were able to clean the electrolyte fluid/gunk off the board and the traces aren't corroded or damaged, swap the electrolytic capacitor with one of the same rating making sure you put it back in the right direction as it is polarized. This is a common part to fail as they start to bulge or leak over time and that cartridge can be up to 25 years old. Even if it hasn't leaked yet and isn't bulging, you might wanna replace it as a preemptive safety measure. But, do this after you do the tests listed below to make sure you aren't wasting your time.

If the cap didn't look destroyed, then check continuity from the pins of the Mask Rom and the CIC to the edge connector to make sure they actually getting their signals out there. If that is fine, test the resistors (Rarely the issue and probably gonna be fine but takes all of 2 seconds to check and doesn't require removal from the circuit.) If all that is good, swap the electrolytic capacitor taking the precautions mentioned above. If you did all of this correctly and it still doesn't work, then it is probably the CIC (the smaller chip). If it can't communicate with the CIC in the console, then the reset line is held low which would result in a blank screen. You could try swapping the CIC out from a game that you don't care about that you know works. If that doesn't work and you have proper continuity, then your Mask Rom is shot.

 

Just checked the capacitor and there is no bulge or leakage so it appears to be fine.
No problem with the resistor either. I've also just checked continuity between the chips and edge connector and all seems to be good with that as well. Looks like the mask rom is shot☹️
Thanks for the advice btw.

 

I've just done another continuity check and I'm not getting continuity between the first contact on the edge connector and one of the corner pins on the cic chip. The current has to pass through the capacitor to get from the contact to that particular pin. Maybe it is the capacitor that's the problem?

 

hi Billly , if you can desolder the Cap and test it with your DMM.

 

Unless you had a power surge or static discharge then your MaskROM is probably fine.

If you can take high resolution photos of both sides of the PCB it might help others identify the problem. Usually the problem is dirty contacts. You said you cleaned them so if it's not that there are some other ideas. The CIC chip not functioning will result in a blank screen. It would be unlikely that it would have failed but it's possible. If you had an appropriate adapter device to use a second cart's CIC as if it were an import you could test that. Or if you had a console with the CIC disabled.

One possibility is maybe a trace is damaged generally near where the plasic shell closes around the connector.

I wouldn't start desoldering or soldering anything yet. Identify the problem first. Checking all the connections to the edge connector is a good start.

 

I'm actually using it on a console with the cic disabled.

One problem that I've found is that I'm not getting continuity between the first contact on the edge connector and the corner pin of the cic chip. The capacitor is between the two so does this mean that the capacitor could be dead?

 

it could be the Cap or a broken trace , using a torch or desk lamp and placing it underneath the PCB will help locating a bad trace.

 

The traces are all intact so it looks like it could be the cap. Just seems strange that there is no bulge or leak, it looks to be in good condition.

 

Caps can fail without bulging or leaking. They just diminish in capacity over so many years. Just swap it out and go from there.

 

Just so you know, it's normal for capacitors to break continuity. That's how they are designed.

 

Just desoldered the capacitor and tested it with dmm. I got a reading of 20.7. The capacitor seems ok, is worth still changing it or does it now look like its something else that's the problem?

 

well if you've desoldered it, you might as well replace it.

 

That was the plan but the new cap is fatter than the old one, which doesn't allow the the cart shell to close properly. I suppose I can attach the cap via a piece of wire attached to each leg and then position it somewhere where it fits. Won't look very good though.

 

The cartridge also works without the big capacitor. You might have to concentrate on the traces - there might be a trace which is broken for any reason. Grab yourself a pinout of the Mask-ROM, the CIC-key and the edge connector (cartridge slot) and check continuity for each connection.

Maybe you could share some high detailed pictures!?

There are no resistors on the PCB!

 

Borti beat me to it. Upon further inspection of the PCB that would be in a SCIV cart, those are not resistors, but rather ceramic axial lead capacitors. Sorry for the mix up, I quickly looked at the picture on my phone and didn't zoom into the board enough to where I could see the markings that say C2 and C3. While they don't commonly fail, ones that aren't functioning properly, or aren't making contact in the circuit would cause a game not to work. Since they are ceramic types, they don't contain electrolyte so they will not exhibit physical symptoms of failure such as bulging or leakage like an electrolytic capacitor will.

 

Just tried to post a photo of the board but it won't allow me to. Trying to post from an iPad but it says the the file doesn't have a valid extension?


I've checked continuity from chips to edge connector and they are fine. I've also just changed the electrolytic cap for a new one and the cart still doesn't work, just get a black screen.

 

if your familiar with soldering and desoldering you could try desoldering the maskrom and swapping it onto a known working PCB, this would eliminate all other factors (except it being a console fault)

so yeah maybe first try a different console, then if you want to swap the maskrom over to another matching PCB

 

I've tried a different console and still no joy. Not sure that I've got another matching pcb, I'll have a look and maybe try that although I'm not sure it's worth risking breaking another cart.

It's all a bit worrying really as I've spent a lot of money in recent years on nes and snes carts. Makes you wonder how much more life they've got left in them.

 

http://www.snescentral.com/pcbboards.php?chip=SHVC-1A0N-01

That is a page that has info on your PCB as well as a list of the games that use it. Maybe you got a copy of the Addams Family or John Madden Football that you don't care about to try a swap with. I hope you get it working as SCIV can be somewhat pricey, as well as an excellent game.