Name that car noise

February 21, 2017 11:10 AM

When I ride in my husband's car I hear a continuous noise like a camera flash charging. It's that really high frequency, rising pitch noise that lasts maybe 10 seconds per cycle, and cycles the entire time the car is running. My husband doesn't hear it. The car is a 2016 Honda Accord. What might this be?
posted by Kriesa to Technology (14 answers total)

Is it a hybrid? I would describe a sound I've heard hybrids making as a camera flash charging sound.
posted by brainmouse at 11:15 AM on February 21, 2017

Is this an Accord Hybrid?
posted by thewumpusisdead at 11:16 AM on February 21, 2017

Do you have a phone charger plugged in? Mine does this if it's not connected to a phone.
posted by mattamatic at 11:19 AM on February 21, 2017 [1 favorite]

It could be the LTE antenna on your phone interacting with the stereo console. Ours *occasionally* does it and we have a Mazda3.

nthing the hybrid, as well.
posted by Tardis_Spin at 11:21 AM on February 21, 2017

Response by poster: Thanks. It's not a hybrid, but it does have an "eco mode" which my husband generally has on. The car is pretty new to us and I don't ride with him that often, so I haven't observed if it happens when "eco mode" is off. It does happen when the phone charger is not plugged in.
posted by Kriesa at 11:31 AM on February 21, 2017

Is the parking brake engaged? That makes a sound sometimes.
posted by any portmanteau in a storm at 11:45 AM on February 21, 2017 [1 favorite]

I have this on my car which is an older (non-hybrid) Honda CRV but it happens only occasionally, usually when I am driving at certain speeds. Am curious to hear what others say.
posted by jessamyn at 12:10 PM on February 21, 2017

It cycles the entire time the car is running? Do you mean that say that it repeatedly sweeps from a lower pitch to a higher pitch, over and over again? Or does it start at a low pitch, rise to a high pitch, and stay there? Does the pitch vary with vehicle speed?

Does his car have a CVT (Continuously Variable Transmission)? The CVT is optional across the board, standard on the EX-L, and on both Accord EX-L V-6 and Touring. The CVT has been identified as a source of a continuous whine, which could be similar to what you're hearing.
posted by the Real Dan at 12:12 PM on February 21, 2017

Response by poster: Do you mean that say that it repeatedly sweeps from a lower pitch to a higher pitch, over and over again?
Yes, this.

No CVT.
posted by Kriesa at 12:53 PM on February 21, 2017

In a camera flash, that sound is a bank of capacitors charging from a battery to power the flash.

Some Hondas have a large capacitor which charges up to assist the start of the air conditioner compressor in a similar way when the thermostat turns the compressor on.

But I wouldn't think such a charger would run continuously unless there was some problem in the capacitor assist system.
posted by jamjam at 12:54 PM on February 21, 2017

A turbocharger makes a high-pitched whistling noise, typically while accelerating, but my cursory googling suggests that that's not an engine option available on 2016 Accords (but perhaps available in 2017 models?). In my experience, not all people can hear (or don't notice) the sound.
posted by strangecargo at 3:02 PM on February 21, 2017

Is the radio on? If so, turn it off and see if the sound goes away. You maybe hearing alternator whine (Google alternator whine or car radio whine).
posted by Carbolic at 6:51 PM on February 21, 2017

If you start the car, leave it in park, and turn off the radio and ventilation, does it still make the sound?
posted by Juffo-Wup at 1:23 PM on February 23, 2017

I have been listening for this on my car for the past few days. On my car I only hear it when I am

- traveling uphill
- between 3100 and 3200 RPM

But I can almost predictably make it happen given those parameters.
posted by jessamyn at 2:25 PM on February 23, 2017