Will do. Just arrived home this evening. Will submit this weekend. Headed south on Monday for the holiday, so I will have warmer temps next week.
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Cold Weather Pre-conditioning not working?
- Thread starter CraDavis
- Start date
Will do. Just arrived home this evening. Will submit this weekend. Headed south on Monday for the holiday, so I will have warmer temps next week.
Seattle Tom
Member
I have no evidence to back this up, as it’s only been noticeable for the past month or two when the weather turned, but I think Tesla nerfed the battery heater function during that spate of fires that occurred this spring/summer.
I doubt the fires were caused by that feature (though maybe Tesla saw something we never heard of), but rather it helped eliminate a potential cause of issues at a relatively low cost of customer inconvenience for the first several minutes of driving with no/limited regen. Just a thought!
I doubt the fires were caused by that feature (though maybe Tesla saw something we never heard of), but rather it helped eliminate a potential cause of issues at a relatively low cost of customer inconvenience for the first several minutes of driving with no/limited regen. Just a thought!
Just submitted service request. A related issue I’m experiencing is that periodically I can’t get the Climate to turn on remotely. That happened in NJ. Rebooting MCU didnt help. Visiting Supercharger did. Next day is when I discovered no battery pre-heat. Now I’m home. Car plugged in to UMC in garage and today I can’t get Climate to turn on from mobile app. Mobile app works - I can do other things. Leaving Monday for South Carolina. 1st available service appt is Jan 9th..
Mid December I submitted a ticket to Tesla customer support for; software and app support option describing the issue. Heard back in Late December. At this point I further described the problem to the customer service rep., and sent them some more data and a fairly lengthy description of the issue and why scheduled departure is not the solution blah, blah, ...
They suggested I book a service request with my local service center. Instead I sent the techs there an email asking if this were a real request that they could even help with as it appears that this is more of deliberate software change. The response I received was that there was no need to book service, there was nothing they could do, and that this was an intended change to behavior of the code. They did mention that they would try to get a message to the engineering team but I expect that this is a one-way message and will not hear back.
My suggestions (mentioned to customer support rep.) to bring back the functionality includes some enhancements:
The loss of energy that initially occurs while driving in cold temperatures amounts to ~10 kms of range loss just for battery pre-heat alone. Loss of reGen is equivalent to 1.5x battery pre-heating loss as far as I can tell, for a total loss of 25 kms. On a trip this is roughly 7% of 400 kms (250 mi) range on the first leg - the difference between making it to the first supercharger (125 mi) or not, and if weather is poor (heavy snow for example) you wont make it more than 50% of advertised range, at least 57% would be a big big difference.
They suggested I book a service request with my local service center. Instead I sent the techs there an email asking if this were a real request that they could even help with as it appears that this is more of deliberate software change. The response I received was that there was no need to book service, there was nothing they could do, and that this was an intended change to behavior of the code. They did mention that they would try to get a message to the engineering team but I expect that this is a one-way message and will not hear back.
My suggestions (mentioned to customer support rep.) to bring back the functionality includes some enhancements:
- Set battery pre-heat temperature based on the following:
- IF charging is set to 'Trip', set battery pre-heat temperature to 21°C
- If charging not set to Trip and outdoor temperature is > 0°C set battery pre-heat temperature to 12°C
- If charging not set to Trip and -10°C < outdoor temperature is <= 0°C set battery pre-heat temperature to (12°C + 0.5*-1*OutdoorTemperature)
- If charging not set to Trip and outdoor temperature is <= -10°C set battery pre-heat temperature to 18°C
The loss of energy that initially occurs while driving in cold temperatures amounts to ~10 kms of range loss just for battery pre-heat alone. Loss of reGen is equivalent to 1.5x battery pre-heating loss as far as I can tell, for a total loss of 25 kms. On a trip this is roughly 7% of 400 kms (250 mi) range on the first leg - the difference between making it to the first supercharger (125 mi) or not, and if weather is poor (heavy snow for example) you wont make it more than 50% of advertised range, at least 57% would be a big big difference.
aesculus
Still Trying to Figure This All Out
But is that not one of the reasons that Tesla offered Range Mode? For normal driving it would turn on the battery heating but at reduced range. For longer trips you had the choice of turning on Range Mode to eliminate (reduce?) the battery heating in favor of more range.
I use Range Mode on one critical leg of a trip where the charger distance is large, the temperatures are generally 20F and I usually have a headwind and sometimes snow. There is no braking on that leg until the end so regen is not a concern.
I wonder if Tesla is just trying to show increased range on these cars and don't care about consistency of the driving experience. I also suspect Range Mode is not being used by most people as it is sort of confusing and hidden.
Yes, I hear you, and I have tried to 'get' what range mode actually does (and doesn't do). One of our local techs said; 'all range mode does is limit the cabin heater to 3 kW instead of allowing it to go to 6 kW' and prioritizes the front motor over the rear. But is that it? Perhaps I should try to capture some data on the difference.
Without regen, of course on a longer journey you would typically be on a highway and yes you are right the regen isnt that useful until the end, ... again it would be good to gather some logs here to see just how much energy is recaptured on a normal drive highway drive with range mode on/off.
And to be clear, what I want to see is that the functionality return to what it did last year(s), and that is; the battery pre-heat to run in parallel with the cabin pre-heat when started from the app, at the moment it doesn't do that (any longer). Battery pre-heat doesnt start until the vehicle is put in Drive - the battery (like this morning) is (was) stone cold at -12°C. Totally different driving experience when reGen is at 0 kW for the first 18 mins of driving.
Without regen, of course on a longer journey you would typically be on a highway and yes you are right the regen isnt that useful until the end, ... again it would be good to gather some logs here to see just how much energy is recaptured on a normal drive highway drive with range mode on/off.
And to be clear, what I want to see is that the functionality return to what it did last year(s), and that is; the battery pre-heat to run in parallel with the cabin pre-heat when started from the app, at the moment it doesn't do that (any longer). Battery pre-heat doesnt start until the vehicle is put in Drive - the battery (like this morning) is (was) stone cold at -12°C. Totally different driving experience when reGen is at 0 kW for the first 18 mins of driving.
Since the temps dropped in the GTA to around 10 C below zero, I'm losing between 35 to 40% range.
The scheduled departure thing is just useless in my opinion as I don't have any regen for a minimum of 40 mins or mixed city and highway driving.
As someone already mentioned, daily drives to work is not impacted but if you want to go on trip and the distance between SC's more than 240 km (100% charge on my car is 392 km) , good luck going on a trip.
The scheduled departure thing is just useless in my opinion as I don't have any regen for a minimum of 40 mins or mixed city and highway driving.
As someone already mentioned, daily drives to work is not impacted but if you want to go on trip and the distance between SC's more than 240 km (100% charge on my car is 392 km) , good luck going on a trip.
... saw this video on David Drives Electric youTube channel:
Interesting tip (right near the end of the video): If you live within a relatively short distance of a supercharger, you can make that your destination and with the pre-heating needed for faster supercharging, you battery will continue to heat above 12°C pre-heater cutoff, and you get your regen back.
Benchmarking this week: I went from ~300 Wh of regen total for the trip to ~ 2 kWh with the pre-heated warmer battery on the commute to work and back, ... interestingly this is roughly the energy I measure it takes to heat the battery from stone cold (below -10°C) to the pre-heat cut-off limit of + 12°C. So, it may be able to neutralize the losses.
Oh I wish Tesla would simply bring back battery pre-heating in parallel with cabin pre-heating, instead of us trying to find ways to game/trick the software, ... 'sigh.
Interesting tip (right near the end of the video): If you live within a relatively short distance of a supercharger, you can make that your destination and with the pre-heating needed for faster supercharging, you battery will continue to heat above 12°C pre-heater cutoff, and you get your regen back.
Benchmarking this week: I went from ~300 Wh of regen total for the trip to ~ 2 kWh with the pre-heated warmer battery on the commute to work and back, ... interestingly this is roughly the energy I measure it takes to heat the battery from stone cold (below -10°C) to the pre-heat cut-off limit of + 12°C. So, it may be able to neutralize the losses.
Oh I wish Tesla would simply bring back battery pre-heating in parallel with cabin pre-heating, instead of us trying to find ways to game/trick the software, ... 'sigh.
Same boat as the rest. Unfortunately, have had to park outside this winter and only have access to a regular 110v wall outlet. Good news is it charges so slowly that regen isn't ever totally at zero since it's never "fully" charged. My trick is when I get in the car, I switch it to ludicrous and it warms the batteries pretty quickly, even when parked. Bad news is I lose about 20 miles of range leaving it on. Total pain to have to jump through these hoops!
2020.4.1 - battery pre-heat is fixed!
dark cloud
Active Member
Missed this thread amongst the many reduced regen discussions; good stuff! The science background in me wants to know every detail as you are doing, yet the practical side tells me by the time I figured it all out, they change the parameters in the next update and I would have to start all over, so I just drive it as efficiently as possible and not worry about it. Fortunately I don't have to be concerned with a long drive with no superchargers accessible fortunately, the cold weather just means I have to make more stops, and having to plan for that. At least they enabled the battery warming on cabin preheat again with the latest 2020.4.1.
But user adjustable battery conditioning and thus regen maximizing options would be awesome. If I could use shore energy to fully pretreat the car before a long trip, warm the battery as much as possible, and increase the range to a maximum that would definitely ease my wife's anxiety. Like you say a "trip" preheat setting. If she sees that estimated percentage SOC upon arrival get lower than 15% she freaks out. Myself treats the constant balancing of state of charge, driving style and supercharger stops as part of the adventure.
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