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How much balloon noise is acceptable

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I have a service appointment this weekend, and I'll address the issue with them again. Not sure exactly what I can say to convince them, but we'll see...
if you are not happy with their decision, you could visit a different service center or you can move this issue up the chain to a district manager or all the way up to the mothership. the bottom line is that this is a major fault that must be addressed.
 
I've had it pretty noticeable in my car. I only had it at full or near full acceleration. It never bothered me much. Over the two years I had my DU replaced many times (a total of 7 drive units) and it has been getting much better. I think I still have it a little but it's fine. The buzzing noise that I get at normal driving is much more annoying and so far even with so many DU replacements, Tesla has been unable to fix that.
 
If you are talking about the milling noise, a DU swap will fix that.

If you are talking about the balloon squeal, a DU swap will likely have no effect since the sound is emanating from the battery contactors. I, too, had the balloon squeal at high power and eventually my VIN number qualified for the "switch upgrade". This particular update completely resolves the balloon squeal issue, but you only get this update if your VIN number qualifies.
We have similar VIN'S so I asked to see if there was a service bulletin for my car & was told there wasn't that would finally fix the "balloon squeal" after 3 years & 2 DU's, maybe its for the P85's only...who knows.
 
I just had my annual service done on my 70D and complained about the noise.
Here is a portion of the service invoice.


Concern: Customer states: whine of front motor is very loud ( more pronounced between 20-
45mph)
Pay Type: Goodwill
Corrections: Front Drive Unit General Diagnosis
Road tested vehicle. Unable to duplicate customer concern at time. No abnormal front
drive unit noise heard during road test. Slight whine confirmed from front drive unit is
normal operating noise.
Corrections: Front Drive Unit General Diagnosis Conclusion: No Trouble Found
Road tested vehicle. Unable to duplicate customer concern at time. No abnormal front
drive unit noise heard during road test. Slight whine confirmed from front drive unit is
normal operating noise.
 
Tesla just picked up my car for servicing a few items, including the balloon noise (which I started also experiencing intermittently on regen), and when I looked at the service estimate, I don't see anything about a balloon noise, but I do see the following item (note, I never mentioned anything about a power switch when I made the appointment), which further confirms the power switch replacement is the official fix for this problem:

"Concern: Customer states: Proactive Power Switch Replacement - We have been notified this vehicle has been remotely diagnosed that the Power Switch and Power Supply would benefit from the latest generation components."
 
Tesla just picked up my car for servicing a few items, including the balloon noise (which I started also experiencing intermittently on regen), and when I looked at the service estimate, I don't see anything about a balloon noise, but I do see the following item (note, I never mentioned anything about a power switch when I made the appointment), which further confirms the power switch replacement is the official fix for this problem:

"Concern: Customer states: Proactive Power Switch Replacement - We have been notified this vehicle has been remotely diagnosed that the Power Switch and Power Supply would benefit from the latest generation components."

I had my car in for a rim replacement and they mentioned they wanted to change the power switch. After they did that I no longer heard the balloon squeal.
 
Bringing an old thread back from the dead to add some info. I had the balloon squeal in my P85+ from when I first got it as a CPO with around 51k miles on it. I mentioned it during a service visit (for other things) and they basically said it's normal. It would kinda come and go, but overall got much worse over the winter. 15k miles post purchase (66k total miles now) I was back in the shop last week for what wound up being a contactor repair job. Got the car back today, and not a peep of balloon squeal so far. Whatever they did seems to have fixed the squeal completely, the car is silent as a church mouse. It's really nice. So another plug that contactors are the likely culprit of the squeal.
 
Just had my recently-acquired CPO S85 in for various things including the balloon squeal. As typical they explained it as the battery contactors and no repair necessary. I can live with it (even if I don't like the sound), but I really don't want to have a contactor failure out of warranty that could have been prevented!
 
Do you have a typical CPO 4yr/50k mile warranty? If so the contactors will probably fail during the warranty period. It's not a catastrophic failure, you just get a message on the display saying "Reduced power, car needs service". When it happened to me nothing seemed different with the car though. At that point they will replace them, and while doing so you get a fancy P100D loaner. Takes about 2-3 days usually. Once replaced my balloon squeal was totally gone, now my car sounds like the Jetsons car again.
 
Just had my recently-acquired CPO S85 in for various things including the balloon squeal. As typical they explained it as the battery contactors and no repair necessary. I can live with it (even if I don't like the sound), but I really don't want to have a contactor failure out of warranty that could have been prevented!
that's a load of BS, it more than likely is the drive unit and if not addressed can lead to a catastrophic failure, insist on a replacement.
 
A DU failure is catastrophic, but contactor "failure" now is just a error code once the resistance is enough to trigger it. They have tightened the software tolerance up so once it hits a certain threshold you get the "car needs service" note on the screen. Thankfully this happens long before it would fail to a point where you get stuck somewhere.

If your DU unit fails, then yea, you're stuck, but it's not the drive unit making the balloon noise.

/edit. When mine was replaced the service invoice had the following components swapped:
--------------------------
FIELD KIT PYRO FUSE PACK 1.0 1.5 1 (1089619-00-B)

FIELD CONTACTOR KIT W/O FUSE - PACK 1 1.0, 1.5 (1084515-00-B)

Corrections: HV Battery Assembly (Remove and Install)

-Removed high voltage battery to gain access to power switches, re installed high voltage battery after power switch replacement.
----------------------------

Replacing those two things made the balloon squeal go away completely.
 
The milling noise and the Balloon noise are two different problems. Milling is associated with a failing DU, the balloon squeal is most certainly just contactors. My DU was not replaced, just the parts listed above, and the balloon squeal is totally gone now. I've never experienced the "milling" noise so I can't comment on that.

As time goes on Tesla gets a better grip on what causes what. Lots of DU units were replaced early from an overabundance of caution as they sorted issues and began building better units.
When did you get your DU replaced, and did you have both the balloon squeal and milling noise? Was it in the last year?