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Buzz humming sound and drop in charge level

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I've had a non-stop buzzing / humming sound behind my passenger door for days. It occurs when plugged in or not. At the same time, have noticed my charge level drop from what used to be 180 miles to now struggling to get to 170 and usually hanging around 165-163. It's a 2008 Roadster. I've been searching this forum and have seen some comments on cooling fan, but nothing that also had charge levels drop.

Wondering what the experts might think and if there's troubleshooting steps that might make sense. Appreciate the help!

Paul
 
During the Summer my coolant pump stays on constantly for at least a month maybe 2. July and August when the garage stays hot is the problem.

Also while the pump is running there is a fairly large range drop as the Roadster sits there. I have not tried to quantify the range drop, but it could be as high as 10 miles per day.
 
Thanks! Last night I popped the trunk and flipped it to range mode for charge as some of the posts suggested. Left that way for 2hrs or so and then flipped back to standard. It stopped! Must have been the temp then. I don't think I've ever had it in range mode as one odd thing I noticed was the milage immediately jumped up a lot and apparently charged past 200 miles, thought I only had 200.
 
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During the Summer my coolant pump stays on constantly for at least a month maybe 2. July and August when the garage stays hot is the problem.

Also while the pump is running there is a fairly large range drop as the Roadster sits there. I have not tried to quantify the range drop, but it could be as high as 10 miles per day.

get 2 floor fans from home depot; solved the issue instantly no more phantom drain and charging the 10 miles back up daily during summer.

Solution to make car idle during summer times
 
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I've had a non-stop buzzing / humming sound behind my passenger door for days. It occurs when plugged in or not. At the same time, have noticed my charge level drop from what used to be 180 miles to now struggling to get to 170 and usually hanging around 165-163. It's a 2008 Roadster. I've been searching this forum and have seen some comments on cooling fan, but nothing that also had charge levels drop.

Wondering what the experts might think and if there's troubleshooting steps that might make sense. Appreciate the help!

Paul

your car is not going to sleep; read my post above.
 
As Jason says, the car's not sleeping. The key to getting the car to sleep is to get the battery down below 30C, and the trick with Range charging is that it first cools the battery down before pushing more energy into it. That initial cooldown is what you can use, but be sure to stop the charging (or switch it to Standard mode) before the car gets too full. If you let it charge all the way up, you'll be stressing the battery.

I used to do this when I was commuting in the summer. I had free charging at work, so would just charge there, and not at home, but then the car wouldn't sleep properly. All it took was about 30-45 minutes of Range charging to get the battery temp down.
 
The last 2 nights, I have left the car outside all night to cool off. Temperatures outside dropped to 70f on both days, but the pump did not turn off. I then ran a charging cycle during the coolest part of the morning still no luck.

I will try the fans next.
There is a LOT of thermal mass in the battery, so it takes a while (or active cooling) to pull heat out of it. Depending on the temps, that can be more than simply letting it sit outside overnight. Fans should help, but 30-45 minutes of Range charging (240v at 16 amps) will do it a lot more effectively.
 
There is a LOT of thermal mass in the battery, so it takes a while (or active cooling) to pull heat out of it. Depending on the temps, that can be more than simply letting it sit outside overnight. Fans should help, but 30-45 minutes of Range charging (240v at 16 amps) will do it a lot more effectively.

Exactly this. It’s also important to note that while the coolant pump is running, its very own operation creates heat within the pack. If the ambient temp is above 31C and the pump is running, it will essentially work against itself.

I can attest to @jason.tv ’s use of giant floor fans. They can cool down your garage’s ambient temp by a massive amount, and disperse the heat expelled by the HVAC fans running up front during the charge’s cooling cycles. Using these while charging will help the efficiency of the cooling cycles and allow your car to sleep when it finishes.
 
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Exactly this. It’s also important to note that while the coolant pump is running, its very own operation creates heat within the pack. If the ambient temp is above 31C and the pump is running, it will essentially work against itself.

I can attest to @jason.tv ’s use of giant floor fans. They can cool down your garage’s ambient temp by a massive amount, and disperse the heat expelled by the HVAC fans running up front during the charge’s cooling cycles. Using these while charging will help the efficiency of the cooling cycles and allow your car to sleep when it finishes.



right; crazy part is when the car doesn't go to sleep the following day the battery can be 98-102f rather than 82-87F if the car was woken up from sleep state. This is good reason to have OVMS.

This is what caused the bsm isolation faults 283 and 286 when I was doing the new rotor embed process pushing the car hard. Since the HVAC fans turn on while driving to cool down the battery uses even more battery power.
 
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Running a 30 minute range charge and running 2 fans in the coolest part of the day, which was more like 75F did not shut down the pump. Ran the fans the rest of the day and the pump stayed on. Looks like the battery got down to 31C after the charge, but that is it.

You are right that the pump itself may heat the batteries up slowly too. My garage has been around 81 to 83F, but the batteries moved up from 31C to 34C overnight.

Forecast for some cooler mornings in the 60s next week and will try the fans with a charge again then.
 
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Running a 30 minute range charge and running 2 fans in the coolest part of the day, which was more like 75F did not shut down the pump. Ran the fans the rest of the day and the pump stayed on. Looks like the battery got down to 31C after the charge, but that is it.

You are right that the pump itself may heat the batteries up slowly too. My garage has been around 81 to 83F, but the batteries moved up from 31C to 34C overnight.

Forecast for some cooler mornings in the 60s next week and will try the fans with a charge again then.

how many miles did you have till it was done charging? Did you only have 8-10 miles of charge from the phantom drain from the night before? I don't think you are allowing enough time for the battery to be cooled down with the fans. You probably tested range charge for 30 min then switched back to standard and it was near completed right?

Assuming you did above you are trying to cool down a entire battery pack from 95F or hotter in such a small charge time of 10 mile range is not happening; that is your issue.

Take the car out for a spin; use a good 20-25 miles and try again. Standard charge on your normal settings. What kind of fans are you using?

Your battery was right on temperature to go to sleep at 87c but the pump right after charge increased it back up not causing it to go to sleep.
 
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Running a 30 minute range charge and running 2 fans in the coolest part of the day, which was more like 75F did not shut down the pump. Ran the fans the rest of the day and the pump stayed on. Looks like the battery got down to 31C after the charge, but that is it.

You are right that the pump itself may heat the batteries up slowly too. My garage has been around 81 to 83F, but the batteries moved up from 31C to 34C overnight.

Forecast for some cooler mornings in the 60s next week and will try the fans with a charge again then.

When was your last HVAC service? It could help to diagnose if it needs a refrigerant recharge. After all, the HVAC’s effectiveness is the largest factor in ability to cool the ESS.

In those lighter ambient temperatures, your ESS should be cooling itself down below 30C. In my personal experience, as there are two 1.5’s in my garage currently, it’s obvious which one has mediocre A/C. One of them gets to 28C every time it finishes, while the other never makes it below 31C and likes to stay awake.
 
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Jason. You are right, I do not drive the Roadster much. Maybe once a week and even then it is less than 20 miles. I am charging at 24amps so a 30 minute range charge plus my 10 mile loss overnight brought my range up to 217 once switched back to standard. Right now my 3.0 pack is stopping at 214 on a standard charge. The fans I am using are the same ones in your pisture. I bought them at Home Depot on Monday after your suggestions. I will try driving the car tomorrow and then charge with the fans running, but I figure my best chance will actually be next week when the daytime lows drop into the mid 60s.

DeedWest my Roadster is indeed a 1.5. I do not know how much Tesla looked at the HVAC system on its last annual service, but that was 2 years ago, mainly because they do not respond to my service request at [email protected].

The battery temperature has now ticked up another degree to 35C.
 
Jason. You are right, I do not drive the Roadster much. Maybe once a week and even then it is less than 20 miles. I am charging at 24amps so a 30 minute range charge plus my 10 mile loss overnight brought my range up to 217 once switched back to standard. Right now my 3.0 pack is stopping at 214 on a standard charge. The fans I am using are the same ones in your pisture. I bought them at Home Depot on Monday after your suggestions. I will try driving the car tomorrow and then charge with the fans running, but I figure my best chance will actually be next week when the daytime lows drop into the mid 60s.

DeedWest my Roadster is indeed a 1.5. I do not know how much Tesla looked at the HVAC system on its last annual service, but that was 2 years ago, mainly because they do not respond to my service request at [email protected].

The battery temperature has now ticked up another degree to 35C.

If you don't use or charge the car much perhaps dial down from 24A to 16A; this will give the car more exhaust cycles. Sounds like my car as well; it's a weekend car for me so I drive maybe couple times per week.
 
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