The most common problem with an Atari Jaguar is not being able to power it on. Usually this is due to user error rather than a hardware fault, so here’s how to quickly fix the problem.
First things first: the Atari Jaguar power adapter
Before proceeding to my quick fix, I want you to check something. Are you using a power adapter that came with the Jaguar? The most common cause of faults with vintage electronics is using an incorrect power adapter. If you are using an OEM power adapter that says Atari Jaguar on it, skip to the next section.
Substitute Atari Jaguar power supplies
If you don’t have the original power adapter, there are power adapters that will work. But most modern 9 volt DC power adapters have the wrong polarity, and they will damage a vintage game console like the Atari Jaguar. Repair kits are available, but if you’ve never done surface mount soldering before, this isn’t the project I recommend learning on.
What you need for a Jaguar is a 9 volt DC, center negative adapter that can supply at least 1.2 amps. One amp will do in a pinch, but the original was 1.2, so it’s better to go with 1.2 or higher. An adapter for a Sega Genesis or Neo Geo console will work. These days, center negative adapters aren’t the most common type, so don’t just use whatever adapter you have laying around whose plug fits.
If you have several vintage consoles, I strongly recommend putting a very conspicuous label on any AC adapter stating what consoles it is compatible with. That way, if someone else goes to set up one of your consoles, they don’t damage it. It’s one thing if someone damages a Genesis, but another if someone damages a Jaguar. A Jaguar is much more expensive. Just shipping a Jaguar off for repair will cost more than a Genesis costs, because of the insurance involved.
Atari Jaguar won’t power on? The surprising fix
There is one surprisingly common reason why an Atari Jaguar won’t power on when you connect power and push the power button. An Atari Jaguar won’t do anything without a cartridge installed. So unplug it, check your power supply just to be sure it is indeed 9 volts DC, center negative. Besides checking the label, you can confirm with a multimeter.
Then plug a cartridge in, then plug the power adapter in, and try powering it back on.
As long as someone hasn’t tried using the wrong power adapter sometime in the last 30 years, the console should come to life. If it doesn’t, try another cartridge just in case there’s a problem with that particular cartridge.
To avoid any confusion, I strongly recommend making bold, conspicuous labels indicating the correct power adapter to use with each of your systems. You can place the label on the back where it won’t ruin the aesthetic of the machine, and you can put the label on the least conspicuous spot on your AC adapters, but when you have a console that is worth hundreds of dollars, I think taking this step to protect it is well worth it.
Don’t worry about devaluing the machine. Any label that you put on the machine or the AC adapter is easy to remove in the future by swabbing a bit of lighter fluid around the edges of the label.