What the alternator does
It charges your battery and powers your electrical system while the engine runs. When it fails, the car runs down the battery and eventually stalls.
Five warning signs
- Dim or flickering headlights
- Dashboard battery/charging light is on
- Slow or no crank when starting
- Whining or grinding noise
- Electrical gremlins — windows, radio, or dash acting up
Before you buy
Confirm the part fits your year, make, and model — amperage and bracket vary. Use the vehicle selector to see alternators confirmed to fit your car, then compare options.