Outside Temp -26 Deg with limited Regen Braking

[Bengt18T]

So a bit ago I head out to the car to make a quick trip to the house on my lunch break. When I get in it tells me something to the effect of "Regen Limited... braking will become available when driven" like it normally would when it's cold. I thought nothing of it although it is in the 60's here today and sunny. On the way home I notice the red "(BRAKE)" symbol in the upper right hand corner of the display next to where the Parking brake symbol is. Car drove ok, but will less regen braking. Then on the way back from to work I see the exterior temp is showing as NEGATIVE 26 deg F! Yes, NEGATIVE!

I didn't have much time, but did a quick steering wheel reboot, but it didn't help. It's currently 65, sunny, and warm in the car but the interior temp on the Tesla app is occasionally alternating between the high 30's and high 60's.

Anyone ever see anything like this? I'm going to try a screen reboot after work. I'm just hoping that it's not trying to heat the battery thinking it's sub-zero when it really warm to begin with.

Thoughts or recommendations?

 

[jcanoe]

This sounds like a faulty outside air temperature (OAT) sensor. If the vehicle was older, I'm assuming this is a brand new Model Y you are driving, I would suspect the 12V battery is failing.

 

[Bengt18T]

Yes, a 1 month old Model Y. Just tried a brake and buttons reboot, but still the same. Let's see if it's that way when I have to leave.

 

[PatinCT]

My first thought was the scenario from “The Day After Tomorrow” where the temperature of the earth plummets. Whew.

 

[TSLA Pilot]

Call Tesla's customer support number when this is going on: they can capture data from the car in real time and help diagnose the repair.

They have "Virtual Techs" to help save time when the mobile service techs show up; clever idea!

 

[Bengt18T]

Update... so after an hour and a half on the phone with Tesla yesterday evening, several more reboots and power downs, nothing has helped. It definitely needs to go in for service to look at.

Here are the new symptoms from the commute home yesterday. Indicated interior temp from the app has gotten down as low as -7 deg. So if the HVAC is on in any setting (auto, manual, lo, etc.) it blows as hot of air as it can... probably because it thinks it's well below freezing. Regen and brake error messages are still present and the heat pump sounds like it is constantly heating the battery even when warm and parked. This is what scares me the most. Overheating it due to a faulty sensor, not that I expect Tesla to ever admit that.

So, since I guess Tesla thinks central PA is a deserted wasteland (even though I live on one of the busiest corridors in the northeast), the nearest service center (4 different ones actually) is a bit over 1.5 hours away and offer no mobile services. They don't even have any towing providers on their "preferred" list for the area. I was put in touch with Tesla roadside and after some convincing, having them looking for a tow to the service center. Since everything is on rest coast time, I'm currently waiting on my Tesla roadside guy to get into the office, hopefully find a tow provider, and get the darn thing to service before it heats itself into a fusion reaction.

If I had to guess, I'd say the problem is either with a faulty temp. sensor or the heat pump/hvac system causing a cascade effect, but who knows.

Overall, I totally LOVED my car... until yesterday. Now I'm pretty bummed. Even if they tow it, fix it, AND bring it back (which I'm guessing probably won't happen), there will still be a monetary cost for work time lost dealing with everything and fuel costs driving a borrowed ICE vehicle, not to mention the complete aggravation of it all. I will say that both the Tesla support and roadside people I spoke with were very nice. That is always refreshing.

I mean, come on Elon... I at least expected a little more than a month before things went all bat-*sugar* crazy. So in the mean time I'm driving a 17 year old, full sized pickup that has never once had a problem with the thermostat, outside temp, hvac, or braking for a small fraction of the cost. Antiquated yes, but works every time the key is turned.

I'll share more as things evolve.

 

[Bengt18T]

So I was completely wrong. Initial inspection from the service station is squirrels chewed a few wires and were storing things inside under the frunk. I love nature and never had any issues with them around the house until now.

No garage so the car is permanently outside. Now I'm not even sure what to do.

 

[LNL_HUTZ]

Now I'm not even sure what to do.

May I suggest squirrel poison?

 

[Bengt18T]

If it comes down to it, possibly. Or a spring trap.

 

[DanDi58]

So I was completely wrong. Initial inspection from the service station is squirrels chewed a few wires and were storing things inside under the frunk. I love nature and never had any issues with them around the house until now.

No garage so the car is permanently outside. Now I'm not even sure what to do.

There are some sprays you can buy that you'd probably need to do every so often - spray the 'under frunk' area with them.

I had a similar issue with my '76 MGB, which was sitting in my garage for about 5 years before I shipped it off to get fixed - opened the hood and found that it had been used by squirrels as a home for a while.....

 

[Jacopa]

.22 ammo is cheap.

 

[DSolie]

.22 ammo is cheap.

Is it? In the PNW prices are getting out of hand... again...

 

[Jacopa]

Actually that's very true, same in New England. And forget about 9mm.

 

[Bengt18T]

Hunting them is a no go. It's in town with a ban on shooting. BB or pellets is not really a good idea either with neighbors 360 deg around the property fairly close by. And not even enough physical space to build a garage, or it would have already been done.

Thoughts at this moment are the repellant spray on the car combined with trapping and/or baiting them. Frustrating because in the 13 years of living there not once have they bothered my other vehicles or my neighbors that I know of.

Haven't heard any more back from service but did get a notice a part was order for the vehicle. Looks like a replacement harness. With parts being ordered I anticipate the car being out of commission for a while until it comes in. Not exactly to excited to hear what the estimate for repairs is though. I'm guessing probably enough to turn into insurance.

Part ordered:
ASY,HARN,FEM,MY
Part #: 1489050-00-C
Order Date: October 7, 2020

 

[DMC-Orangeville]

Petroleum jelly (or similar product that won't damage cable insulation) with hot pepper sauce works well too. Smear some of this on exposed wires.....but wear nitrile gloves while applying

 

[MP3Mike]

Honda makes an anti-rodent tape that you can put on the wires: 4019-2317 - Genuine Honda Tape,Rodent 19MM 20M

 

[Bengt18T]

The wires are completely inaccessible with out removing pieces of the frunk and undercarriage... unless you're a rodent of course. That's why I'm thinking a repellant spray with a wand that can reach behind the underbody shields and other areas.

 

[LNL_HUTZ]

How about a regular supply of squirrel food under a neighbor's car?

 

[Bengt18T]

Spoke with the service advisor again. Not as bad as expected. The harness should take about a week or so and he said it shouldn't be too hard to install. All in, he's thinking about $500 bucks. I'll take it.

 

[Bengt18T]

Conclusion... car is back. They put a rush on the harness since the car was not drivable. I couldn't be happier with Bill at Tesla service in Lancaster, PA.