A long time ago, the Suburu alternator had a relatively easy job to do. All your alternator had to do was run the horn, heat blower, lights, and battery to keep the car going. The modern cars of today require much more from their alternators. Where old alternators needed to generate between 50 and 60 amps to power their vehicles, newer alternators are expected to put out 100+ amps to take care of all of their accessories. Think about it: you've got luxury items such as heated car seats, HID headlights, high-amp stereos, and even moon roofs to power with your alternator. That's not including the essentials like the battery and engine fans. With all these extras to look out for, replacing your alternator at one time or another is inevitable. There's no warning sign that your alternator is going bad and there are many reasons why an alternator dies.