What Are Some Signs That an Alternator Is Going Bad?

Signs that an alternator may be going bad include a weak battery, dim lights, strange sounds and smells or warning lights on the display panel reading showing the picture of a battery or displaying the codes "ALT" for alternator or "Gen" for generator. Alternators are part of the electrical system in cars and work by providing power to the batteries. If owners suspect a problem, they should have their alternators evaluated quickly because dead alternators can leave drivers stranded or mean extensive repairs, say experts at PepBoys.

Because alternators work directly with the electrical system, dimming lights are one of the first and most distinct signs of alternator problems. Alternators help power the ignition, starter and electrical accessories in cars. As alternators lose power, drivers may notice their cars take longer to start. Headlights may be dimmer, along with display panel lights. Electrical accessories, like windows and seats, may also function more slowly than usual, say experts at PepBoys.

Sometimes, dimming lights indicate a battery problem. Like alternators, batteries have limited lifespans and may need replacement. Drivers can distinguish between the two problems by first replacing the battery. If the problem persists, a failing alternator is likely the problem.

Failing alternators may also cause friction, which creates a smell of burning rubber. Worn down parts and components that help turn alternators, such as bearings, may cause unusual sounds, such as grating and grinding. Lastly, owners may look for alternator problems by inspecting the surrounding belt; loose, tight or cracked belts indicate a problem.