Q: Loud humming noise

asked by on August 16, 2016

I had a low battery in my CLK500 and got it charged just recently. Then it started doing this loud humming noise right after I had been driving and then turning off the car. This never happened before. It doesn’t do this every single time but off and on quite often. What could this be? Should I take my car into the shop?

Alternator Replacement $166.62 - $1297.14 Get a Quote
Electrical components are not working Inspection $94.99 - $114.99 Get a Quote

Hello. There could be a problem with the alternator not charging properly, causing low battery voltage. This could cause electrical components to come on and off when they shouldn’t. The alternator could be making the humming noise you hear if the bearings are going bad. I would suggest that you have a certified technician, complete an inspection of the electrical system, in order to pinpoint the problem and recommend the necessary repairs.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

What do the error messages mean when playing a USB device?
Your car’s audio system can display a number of different error messages when something goes wrong while playing files or connecting to your USB flash memory device. Below, you’ll find a brief summary of these. USB Error: This means that...
How do you use Dual Zone Automatic Climate Control with the in-dash navigation system?
If you have a built-in navigation system and your car also has Dual Zone Automatic Climate Control, you’ll find that operating the system is a little bit different from either the manual climate control or the non-navigation based Dual Zone...
driver's door ajar light will not go off, computer not working, reset button does not work
The drivers door ajar switch is mounted on the door latch inside the driver's door. If you check the striker where the latch hits in the door jam to see if it was moved. You should be able to see...
My car is only yielding 11km/liter - what should I do?
Hello. A 2016 Impreza 2.0 should yield 28 mpg city 37 mpg highway. If it is only yielding 11 KM/L at 120 KM/PH then there is likely an issue with the vehicle, as it should be yielding close to 15...
Check Engine Light is on, trouble code P0011&12. I changed the oil and filter. I need to turn off the engine light to see if that problem is solved.
Hello. If the oil level was low or if the wrong oil war previously used then that can cause these codes to come up. Most of the time though, on this engine, it is caused by a failure in the...
Heater blows luke warm air.
The [heater core]((https://www.yourmechanic.com/services/heater-is-not-working-inspection) is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant to heat the inside of the car with the help of the blower...
Runs rough & Engine light
The codes being set should be investigated first unless they implicate systems or components that clearly are irrelevant as "causes" of a rough running condition in which case you would diagnose and fix the rough running condition first and then...
car shakes when i start it in the morning, check engine light blinks then stays on
If you have the engine computer scanned you most likely have a misfire code to one or more cylinders. You may have a bad plug wire or coil or spark plug. If you have not got a tune up then...
Car won't start. Clicky sound happens. Windshield wipers go on own. Horn won't honk upon locking car
Hi Mary. Thanks for contacting us today. What you are describing is commonly caused by a damaged electrical relay or an electrical short circuit within the steering column. In some instances, it can be a combination of electrical problems, such...

Related articles

How a Car's Cooling System Works
Have Have you ever considered the thousands of times explosions occur in your engine? If you're like most people, that thought never enters your mind. Every time a spark plug fires, the fuel and air mixture in that cylinder blows...
A Buyer’s Guide to the 2012 Mercedes-Benz C-Class
The The Mercedes-Benz brand is synonymous with luxury, and the vehicles in their C-Class from 2012 are no exception. Key Features A great feature of the 2012 Mercedes-Benz C-Class is the attention assist built into the vehicle. This will actually...
A Buyer’s Guide to the 2012 Mercedes-Benz SLK
It’s It’s not a sedan and it’s not quite a sports car, but chances are that brand-loyal fans desiring that luxury-class hard-top convertible with some oomph under the hood won’t care. The SLK roadster boasts three attractive engine options, and...