How does an N64 cart go bad?

[pakopako]

One the questions I have in the recesses of my mind. I'm pretty sure I have a Mario64 cart that can't be read by my console. Even opened the cart up and stuck the PCB into the slot; No Joy.

As far as I can tell, no one but me has even tried to open the cart up. The pins are all in good condition. The console works with other games. I just can't tell why this game won't work.

[DinnerX]

The pins are clean right?

Have you tried pulling up on the cartridge? I have a few carts that will not start unless you power up the console with the cartridge pulled up nearly to the point of being out.

[Ziggy]

I haven't taken apart many N64 carts so it's not clear in my memory, but some times when you take the PCB out of the shell and stick it in the console, you can actually push it in too far. If you look at the console's cart slot, look at the way the pins are shaped, they have almost a single point where they make contact. If you push the PCB in too far, so the pins of the cart go past that point, then it's not making contacting with anything. I've learned this the hard way with Famicom carts. Wasted the better part of two days figuring out why a cart wouldn't work, I only realized when I finally put the PCB back in the cart shell and it worked again.

Anyways, if the cart doesn't work in the cart shell, it's not like it's gonna magically work out of the cart shell. When you opened the cart up, did anything look wrong with the PCB? If you have a camera, open the cart up again and take a pic of the front and back of the PCB. Make sure to take a CLEAR shot of it, and post the highest resolution you can.

The next step, after not being able to find a problem visually, is to go to town with a multi meter.

[pakopako]

Well, here's the largest I'd want to upload them.

The next step, after not being able to find a problem visually, is to go to town with a multi-meter.

I thought it might come to that. I think I still have an old battery-less analog one, but I don't think that would measure anything but current. Any recommendations on multimeters that don't use 9-volts or C-cells? (And what range of values to expect when poking around.)

[cookie monster]

Try cleaning the pins with a toothbrush and alcohol then wipe dry with a q tip some times it is just a piece of crud that is hanging on. I have had this happen once or twice.

[pakopako]

Did the images need to be at a higher res?

[Ziggy]

Well, here's the largest I'd want to upload them.

Did the images need to be at a higher res?

The images are fine. I just got in the habit of telling people to upload clear, high res pics because sometimes some one will post a blurry cell phone pic and it's hard to make out anything at all. The pics you posted are perfect. The only thing, I can't see the top of the capacitor. It's probably fine, but take a look at it and see if it's bulging. This is an illustration of a good and bad cap (good is on the left - flat top, bad is on the right - bulged top). And here is a pic of a cap with a bulging top.

Try cleaning the pins with a toothbrush and alcohol then wipe dry with a q tip some times it is just a piece of crud that is hanging on. I have had this happen once or twice.

That's sound advice. With the cart opened and the PCB out of the shell, dampen a toothbrush (or whatever you have handy, like an old t-shirt, just make sure whatever you use is relatively clean) with rubbing alcohol and scrub those pins really good. You don't really have to worry about drying it, the alcohol will evaporate pretty fast, especially a rubbing alcohol that has a higher content of alcohol. But you'll wanna wipe the pins after the scrubbing, before the alcohol evaporates. An old t-shirt will work fine for this, just visually check afterwards to make sure you didn't leave any lint behind.

The next step, after not being able to find a problem visually, is to go to town with a multi-meter.

I thought it might come to that. I think I still have an old battery-less analog one, but I don't think that would measure anything but current. Any recommendations on multimeters that don't use 9-volts or C-cells? (And what range of values to expect when poking around.)

Any particular reason why you would want a battery-less multimeter? A meter that doesn't use a battery wont be able to measure resistance, so continuity checks will be out. And you really wanna stay away from analog meters. They might look neat, but they're a pain in the ass to work with.

This is the cheap multimeter I've had for years, and it never let me down. It only measures AC/DC voltage and resistance, but that's enough. It doesn't have a continuity setting, but you can still check continuity with a resistance setting.

I assuming that the N64 supplies 5v to the cart, but I could be wrong (it might be 3.3v for example, I never checked). An easy way to check would be to power on the N64 then touch your probes to the ground and voltage pins on the cart slot. But here's a huge warning: When ever you're probing something that's powered on, be VERY careful. If you accidentally bridge two connections together, you can easily blow something out. I actually wouldn't recommend doing this unless you have experience with such things.

[pakopako]

The only thing, I can't see the top of the capacitor. It's probably fine, but take a look at it and see if it's bulging.

No on the buldge, but I'll have to double check somewhere down the line to make sure it's still holding a charge. And no dice on the dirt; I make double-sure all my device-connectors remain clean.

Any particular reason why you would want a battery-less multimeter? A meter that doesn't use a battery wont be able to measure resistance, so continuity checks will be out. And you really wanna stay away from analog meters. They might look neat, but they're a pain in the ass to work with.

Yeah; I've still got an old analog one, but the reason I don't like the battery-powered ones are that they usually only take 9V batteries instead of AA's that I can user interchangeably with other devices.

I've been out of the loop for awhile, but what's testing continuity? (Ah, nevermind. I used to 'test for shorts'. I still remember how resistor color-coding works, so I can at least match up ohm readings if I get a multimeter.)

I'll try my luck after PAX to see if something's up with the objects on the board. I wonder if this means something on the ROM chip is toasted?