Continuous Faint Humming Noise When Parked

[hgmichna]

I noticed this early on, after I got my Model 3. I can hear it best when leaning over the windshield wiper opposite the driver side. I have read quite a bit about it and concluded that it is normal and healthy behavior. It is not loud at all, and I usually don't hear it any more, probably because I got used to it.

It stops after a while. It always stops when the car sleeps.

 

[RayS85]

Yes, I am sure it is all in this thread, but I haven't read these posts in a while, and Tesla is always changing how the car behaves with progressive updates.

The coolant pump will run for a while if you store the car at anything greater than about 77%, (latest SOC level a few of us have observed) to provide thermal equilibrium in the pack to prevent one cell or group of cells from being stored at potentially dangerous temperatures while at a relatively high state of charge. After the spontaneous fires from at least one parked car (the one from the underground in China) this has been employed by Tesla.

I am sure the ambient temperature someone has parked the car in has something to do with this number; what was the temperature where you parked the car?

It should have stopped after several hours, and it is fine, but if you don't need the 10% charge level on a daily basis or don't want to hear the pump just have the car at SOC of 70% and you probably won't hear it after charging. If the car is charging of course you will hear the pump circulate coolant.


One thing is certain, the more parts are used the quicker they will wear out; every moving part has a life.

Thanks for the update on this issue. I am very able to live with it, it’s just annoying. I don’t care about the sound itself but I don’t like the fact that it drains the high voltage battery. The temperature on the battery I don’t know, I guess it wasn’t on the high side, since I’ve only been cruising in the 60s range and the outside temperature was around the high 80s.

 

[RayS85]

As @dark cloud and @BigNick have mentioned, this is the new 'norm" with your car and you will need to live with it. It happens when you charge to a higher SOC (the exact maximum varies per car, but high 70% is a good threshold!). In short, your pumps will be running very often and that's intentional (unless there is an issue with your louvers underneath the front grill of your car that causes them to be always in closed position).

thanks guy’s for the update and information. Still think it’s strange that the coolant pump has to run for hours to cool a battery that has been sitting unloaded for a longer duration. Something is a little fishy about this phenomenon.

 

[Droschke]

thanks guy’s for the update and information. Still think it’s strange that the coolant pump has to run for hours to cool a battery that has been sitting unloaded for a longer duration. Something is a little fishy about this phenomenon.

This started after software update 2019.16.x of May 2019 for the older Model S cars:

"... we are revising charge and thermal management settings on Model S and Model X vehicles via an over-the-air software update that will begin rolling out today, to help further protect the battery and improve battery longevity.”
Tesla is updating its battery software following a car fire, claims improve longevity - Electrek

 

[OrbiterTI4]

I’m new to TMC because of this thread. I have a 14 S85, and the same issue started for me to day.
...
it’s been running straight for 3 hours now, maybe longer. I have no idea when it started. My GOM says 310km on 80%. Let’s see what happens.

anyone have any idea about what’s up with this?

What's your software version?

I found that after I got an update to 24.6.11, instead of the "run while plugged into charger over 75%" I was previously experiencing/posting about, I now have "run at any point when the battery is over 75%".

This seems true for pre-charging, during charging, post-charging, post-unplugging, and even with the vehicle in drive/motion! My favorite was sitting in the drive-thru line, the battery was at 78% (I had charged to 80% the night before) and I could hear the battery cooling over the noise of the HVAC and radio.

 

[RayS85]

What's your software version?

I found that after I got an update to 24.6.11, instead of the "run while plugged into charger over 75%" I was previously experiencing/posting about, I now have "run at any point when the battery is over 75%".

This seems true for pre-charging, during charging, post-charging, post-unplugging, and even with the vehicle in drive/motion! My favorite was sitting in the drive-thru line, the battery was at 78% (I had charged to 80% the night before) and I could hear the battery cooling over the noise of the HVAC and radio.

My current sw version is 2020.24.6.11 I will give it a try, I will charge my vehicle to 90% now and see if it activates the the pump.

does the pump run for the same amount of time regardless of if the car is plugged in or not? I’ll give that a try too.

 

[RayS85]

This started after software update 2019.16.x of May 2019 for the older Model S cars:

"... we are revising charge and thermal management settings on Model S and Model X vehicles via an over-the-air software update that will begin rolling out today, to help further protect the battery and improve battery longevity.”
Tesla is updating its battery software following a car fire, claims improve longevity - Electrek

Hmmm... maybe they’re installing a hidden sw that prohibits the battery’s ability to use its full potential too. So their warranty claims are reduced. Who knows...

 

[Only Trons]

I just discovered this thread! Lots of useful information in here. Thanks to all who have contributed.

I have an early 2013 S85. Firmware version 2020.24.6.11. I've been having this humming noise for quite a while now. I didn't think to keep a record of it, but I think it has been going on for nearly a year or so. The humming will go on for many hours. And I've been having the same drop in RM as others --- I'll often see a loss of 10 - 13 miles overnight when plugged in. I typically charge my S to 90%. For a while, I was charging to 80%.

In mid 2019, I started noticing errors in the calculation of "time remaining to charge". Model S: Charge Time Remaining calculation is now incorrect I went to the SC. Before I took the car in to the SC, they did remote diagnostics and told me that my battery might need to be replaced. After taking the car in, I was told the battery simply needed balancing. While I didn't believe that was the root cause, I went through a number of cycles to rebalance the battery. Nothing has changed regarding this time-remaining-to-charge-calculation.

I wonder if this calculation issue is related in any way to the humming sound. They both started at about the same time.

 

[Droschke]

Hmmm... maybe they’re installing a hidden sw that prohibits the battery’s ability to use its full potential too. So their warranty claims are reduced. Who knows...

That seems to be the consensus.

 

[Droschke]

I just discovered this thread! Lots of useful information in here. Thanks to all who have contributed.

I have an early 2013 S85. Firmware version 2020.24.6.11. I've been having this humming noise for quite a while now. I didn't think to keep a record of it, but I think it has been going on for nearly a year or so. The humming will go on for many hours. And I've been having the same drop in RM as others --- I'll often see a loss of 10 - 13 miles overnight when plugged in. I typically charge my S to 90%. For a while, I was charging to 80%.

In mid 2019, I started noticing errors in the calculation of "time remaining to charge". Model S: Charge Time Remaining calculation is now incorrect I went to the SC. Before I took the car in to the SC, they did remote diagnostics and told me that my battery might need to be replaced. After taking the car in, I was told the battery simply needed balancing. While I didn't believe that was the root cause, I went through a number of cycles to rebalance the battery. Nothing has changed regarding this time-remaining-to-charge-calculation.

I wonder if this calculation issue is related in any way to the humming sound. They both started at about the same time.

The charging rate for the older Model S cars have been slowed down for a while (you would definitely notice it at the superchargers). The charge time remaining message was never accurate to start with and it's now totally incorrect. These days for cars like yours, if you charge above 70% you will experience the humming noise and range loss. Your battery might need replacement if it can not be re-balanced to an acceptable threshold. Your problem is not unique.

 

[RobK]

We have a 2015 Tesla Model S 85 with about 20,000 miles. Currently it is on firmware 2020.24.6.11

I always set it to charge at midnight (as we get the cheapest rate from midnight to 6:00 AM)). I normally charge when the battery charge shows 65 miles. I set it to charge to 80%. Most of the time it finishes charging by 5:45 AM and I disconnect the charger before we go for our morning walk.

Our car charges to 238 miles at 80%. This has remained the same from the day we bought the can until now.

The humming normally ends by 8:45 AM (i.e 3 hours) when it is parked.

I have observed that when I took the car out for a short distance drive after charging, the humming would stop.

 

[Droschke]

Our car charges to 238 miles at 80%.

Really?

That would be 297.5 miles at 100% on a "2015 Tesla Model S 85". Not possible.

 

[croman]

Really?

That would be 297.5 miles at 100% on a "2015 Tesla Model S 85". Not possible.

Some people like ideal instead of rated. No reason why they should but it happens.

 

[RobK]

Really?

That would be 297.5 miles at 100% on a "2015 Tesla Model S 85". Not possible.

I don't think the battery charge capacity is linear, especially as you get close to 100%.

We have charged our car to 100% capacity and the mileage would show 267. We used to charge the car to 100% going on our trip from Overland Park, KS to Verona, WI. Now with so many supercharges en-route this is not needed.

What kind of mileage do you get at 80% and 100% of capacity?

 

[Droschke]

I don't think the battery charge capacity is linear, especially as you get close to 100%.

We have charged our car to 100% capacity and the mileage would show 267. We used to charge the car to 100% going on our trip from Overland Park, KS to Verona, WI. Now with so many supercharges en-route this is not needed.

What kind of mileage do you get at 80% and 100% of capacity?

193 miles at 80%

 

[RobK]

193 miles at 80%

How many miles at 100% ?

What kind of battery does your car have? 75 KWH?

 

[Droschke]

How many miles at 100% ?

What kind of battery does your car have? 75 KWH?

242 miles at 100%. My car detail is in my signature below:

 

[SeanDog]

I have had the same issue with my 2105 MS 70D. Drove me crazy when it first started and Tesla would not acknowledge that anything had changed. My final solution was to only charge the car to 75% instead of 80% each night. This seems to not trigger the 2 hour pump run post charging.

 

[Droschke]

I have had the same issue with my 2105 MS 70D. Drove me crazy when it first started and Tesla would not acknowledge that anything had changed. My final solution was to only charge the car to 75% instead of 80% each night. This seems to not trigger the 2 hour pump run post charging.

It's called "draingate". It's part of discussion in this thread: Sudden Loss Of Range With 2019.16.x Software

Basically, all older cars (like your model S and mine) are either capacity capped (batterygate), charge rate throttled (chargegate) and/or the cooling pumps running to cool/heat and to drain the excess charge (draingate). They all seem to be interrelated. 70% Soc is a typical threshold for the draingate. Avoid charging to a SoC when you pumps run - stay below.

 

[widodh]

Nice thread this one! I just moved into a new house with a parking garage underneath our house where we park both our Model S (85 from 2013 and 100D from 2018).

My workbench/garage is in the same space and I also started noticing the S85 humming while sitting in the garage idle. This would indeed go on for a couple of hours.

Both cars charge to 90% as a default setting. I also update firmware whenever one is available, so I'm always on the latest one.

I'll keep an eye out, but I'm almost certain mine is suffering from everything else reported here.