Signs your alternator is failing
The alternator charges your battery and runs the electrical system while the engine is on. When it starts to fail, the signs often creep in slowly:
- Headlights and dash lights that dim or flicker, especially at idle
- Slow cranking, or a battery that keeps going dead
- The battery or charge warning light staying on
- Wipers, power windows or the blower fan running slower than usual
- A whining or growling noise from the front of the engine, or a hot electrical smell
If the charge light comes on while you’re driving, the car is running on battery power alone. You may have a short time before it stalls, so turn off what you don’t need and head for the shop or a safe place to stop.
Battery, alternator or wiring?
These parts work as a team, and a weak link anywhere can look a lot like a bad alternator. A worn battery can’t hold a charge. A loose or corroded cable can block the charge from getting through. A slipping drive belt can keep a good alternator from spinning fast enough.
We test the battery, measure the alternator’s output under load, and check the belt, cables and ground connections. That way you don’t buy an alternator you didn’t need, or a new battery that a failing alternator will drain again. If the trouble turns out to be somewhere else in the auto electrical system, we’ll track it down.
What replacement involves
On many cars the alternator sits right up front and the job is straightforward. On others it’s buried under intake parts or low in the engine bay, and the labor goes up. The cost depends on the vehicle, the alternator’s output rating and how much has to come off to reach it.
When we replace an alternator, we also inspect the drive belt and tensioner, since a worn belt can shorten the life of a new alternator. If your car is due for belts as part of its 30K-60K-90K scheduled maintenance, we can handle both in one visit.
Cold mornings and short trips
Pacific Northwest winters are hard on charging systems. Cold weather cuts battery output, and wet, dark commutes mean headlights, wipers, defrost and the heater all running at once. Short trips around Woodinville don’t give the alternator much time to top the battery back up.
If your car starts slowly on cold mornings, have the charging system tested before it leaves you stuck in a parking lot. Company vans and trucks work their charging systems even harder, and our fleet service keeps local work vehicles on the road.
Get your alternator tested
Call 425-420-1630 or request an appointment below. If the car still starts, drive it straight in. You can also leave your keys in our early morning and late night key drop box before or after work.
We’re at the back of Bear Creek Plaza near Hwy 522, and we work on cars, trucks and diesel vehicles of all makes and models.