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Regen has mostly gone. What’s left is intermittent.

15Peter20

Member
Oct 26, 2020
470
2,511
Norfolk
I went to drive the 5 miles home from work tonight and had a ‘limited regen’ warning before I set off. I was surprised as the outside temp was 12 degree C.
During the drive regen slowly crept to about half of its maximum but no more than that. I decided to go for a longer drive but regen available was never more than about half. Worse: if I accelerated hard the available region instantly dropped, making one-pedal mode unusable and unpredictable.
I did a basic reset (wheel buttons and brake pedal) but to no avail.
I’ve tried long, medium speed drives with gentle stopping, harsh blasts with full pedal lift off but no improvement.
I’ve driven in colder temps during my week of ownership and had limited regen but it has always come to life over a few miles of moderate driving. This is something different.
The only thing I have done out of my norm was to sit in it with the heater on over lunchtime.
Any thoughts?
 

DJP31

Active Member
Aug 30, 2015
1,679
1,087
UK
Sounds pretty normal to me tbh. 12 degrees is plenty low enough for the battery pack to be pretty chilly - it took 45 minutes on the motorway last week for me to have full regen. If your normal commute is only 5 miles then limited or even no regen will be a constant until the spring.

You could mitigate by prewarming the car before setting off but I doubt you'll get 100% regen without prewarming for ages, and that's just a waste of energy.
 
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GRiLLA

Member
Jul 5, 2020
840
791
UK
What charge level? You won't get regen above 90%.

How long is long? The other reason for limited regen is a cold battery, the ambient temperature can change much more quickly than the battery. 30-60mins should be enough, as would 20mins of pre-conditioning before you leave.
 

15Peter20

Member
Oct 26, 2020
470
2,511
Norfolk
About 65% SOC. Because the regen didn’t feel as it has over the last few days I extended my drive home to see if it would recover. It did, to about 50%, based on the dotted part of the regen line and the braking was nearly back to normal.

The very odd thing is that the available regen would then drop to nearly zero if I accelerated hard, giving inconsistent stopping dependent on whether I’d just been cruising or had accelerated hard. It has not done anything like this previously.

I’ve driven it in cold weather, down in single digits Celsius and, yes, regen is temporarily limited but it would increase fairly linearly with distance. Today it was erratic and just never achieved full capability but worse, was inconsistent meaning I couldn’t predict the amount of braking available.

edit: I also tried navigating to a nearby supercharger. This started the battery heating process. I then spent half an hour driving without actually going to the SuC. The regen problem didn’t improve.
 
Last edited:

GRiLLA

Member
Jul 5, 2020
840
791
UK
About 65% SOC. Because the regen didn’t feel as it has over the last few days I extended my drive home to see if it would recover. It did, to about 50%, based on the dotted part of the regen line and the braking was nearly back to normal.

The very odd thing is that the available regen would then drop to nearly zero if I accelerated hard, giving inconsistent stopping dependent on whether I’d just been cruising or had accelerated hard. It has not done anything like this previously.

I’ve driven it in cold weather, down in single digits Celsius and, yes, regen is temporarily limited but it would increase fairly linearly with distance. Today it was erratic and just never achieved full capability but worse, was inconsistent meaning I couldn’t predict the amount of braking available.
Sounds odd, I would create a service request in the app, they'll do a remote diagnostic most likely.
 

VanillaAir_UK

Well-Known Member
Jun 17, 2019
8,235
5,759
Surrey, UK
How are you controlling lifting the accelerator?

Say the regen bar had dots to half way. If you lift off fully, then the green line will probably move into the dotted area and you basically get compromised regen - I've not experimented enough to state 'no regen'.

If however, you only partially lift, as would be normal one pedal driving, such that the green bar does not encroach into the dotted area, then regen should be largely unaffected - same caveat as above.

I know that some people drive by fully lifting from the accelerator when braking rather than by feathering the accelerator which many others do. So it may be down to driving style.
 

15Peter20

Member
Oct 26, 2020
470
2,511
Norfolk
How are you controlling lifting the accelerator?

Say the regen bar had dots to half way. If you lift off fully, then the green line will probably move into the dotted area and you basically get compromised regen - I've not experimented enough to state 'no regen'.

If however, you only partially lift, as would be normal one pedal driving, such that the green bar does not encroach into the dotted area, then regen should be largely unaffected - same caveat as above.

I know that some people drive by fully lifting from the accelerator when braking rather than by feathering the accelerator which many others do.

I’ve tried both methods and it is as you say. What is odd is that the dotted part, which would normally decay away over a medium length drive, would abruptly grow, in particular after a hard acceleration meaning the available regen would rapidly reduce. As a consequence next lift off would result in very little regen, ie the car would coast down, feeling like an ICE. It hasn’t done this even in colder weather, other than for the first couple of miles.
 

glide

Active Member
Jun 6, 2018
3,689
3,849
USA
I went to drive the 5 miles home from work tonight and had a ‘limited regen’ warning before I set off. I was surprised as the outside temp was 12 degree C.
During the drive regen slowly crept to about half of its maximum but no more than that. I decided to go for a longer drive but regen available was never more than about half. Worse: if I accelerated hard the available region instantly dropped, making one-pedal mode unusable and unpredictable.
I did a basic reset (wheel buttons and brake pedal) but to no avail.
I’ve tried long, medium speed drives with gentle stopping, harsh blasts with full pedal lift off but no improvement.
I’ve driven in colder temps during my week of ownership and had limited regen but it has always come to life over a few miles of moderate driving. This is something different.
The only thing I have done out of my norm was to sit in it with the heater on over lunchtime.
Any thoughts?
Welcome to winter with an electric vehicle?
 

15Peter20

Member
Oct 26, 2020
470
2,511
Norfolk
Welcome to winter with an electric vehicle?
But it was more wintery last week, in single digit (celsius) temps. 12C is a summer’s evening in these parts.

Nah, something has changed. I got thoroughly used to single pedal driving in the week since collection and I have never had available regen reduce over the course of a drive in mild temperatures until this unexceptional evening. I’d have felt it. Tonight’s regen levels were changing throughout the course of the drive depending on how I’d been driving immediately before slowing the car.
 
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15Peter20

Member
Oct 26, 2020
470
2,511
Norfolk
So no change this morning in spite of a battery pre-condition. Air temp was 9 C as I unplugged, regen showing around 25% but this figure never increased and, like yesterday, abruptly dropped to zero after a long-ish hard accel.

A trip to the SC beckons sadly.
 

VanillaAir_UK

Well-Known Member
Jun 17, 2019
8,235
5,759
Surrey, UK
A long hard acceleration may cause a voltage drop which is really bad for the battery. Its quite possible that they are temporarily protecting the battery by avoiding a mass recharge.
 

JC100

Member
Oct 2, 2020
62
37
Midlands UK
I've only had my car for 1.5 weeks, but had no issues with regen until yesterday and same this morning - wondered if it had something to do with the new software update as it was updated at this time? Difficult to tell for me as not had the car very long, but yesterday and today certainly no colder than before.
 

15Peter20

Member
Oct 26, 2020
470
2,511
Norfolk
I've only had my car for 1.5 weeks, but had no issues with regen until yesterday and same this morning - wondered if it had something to do with the new software update as it was updated at this time? Difficult to tell for me as not had the car very long, but yesterday and today certainly no colder than before.
My software updated last Tuesday (to 48.10 I think) then again last Friday to 48.12. I've done just under 500 miles on the car, with about 250 of those miles on 48.12 and was one-pedal driving almost continuously up until last night. Since then I've had to use the brake pedal regularly.

What is the nature of your issue?

Sorry you've got a problem but if it's the same as mine I imagine that could mean a software, easily fixable fault (or a common electrical/mechanical fault I suppose, but hope springs eternal etc). Is a battery temperature sensor reading faulty for instance?

The fact that mine loses regen capability during highway and high acceleration running suggests some kind of battery or inverter protection as Vanilla_Air suggests above, but the question comes back to 'why now'? .
 

VanillaAir_UK

Well-Known Member
Jun 17, 2019
8,235
5,759
Surrey, UK
2020.48.12.1 has been bulk rolled out. Its an indication that something may be wrong with that version and reliable chat to back that up although nothing mentioned about your behaviour - simply fixes for security and user settings being trashed mentioned so far. Even if there is no published info, its quite possible that something has been changed/tweaked under the hood for the new batteries if thats what you have, so worth checking out to see if .1 is available for you to take.

Regarding battery temperature, even what is warm for humans is still cool for battery. Its not unusual to get regen dots in mid teens ambient - battery is a large thermal mass so temperature changes slowly.

Going back to my comment regarding battery protection, you can also see similar to regen dots on the power used side to indicate reduced power available, although quite uncommon compared to regen side.
 
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15Peter20

Member
Oct 26, 2020
470
2,511
Norfolk
2020.48.12.1 has been bulk rolled out. Its an indication that something may be wrong with that version and reliable chat to back that up although nothing mentioned about your behaviour - simply fixes for security and user settings being trashed mentioned so far. Even if there is no published info, its quite possible that something has been changed/tweaked under the hood for the new batteries if thats what you have, so worth checking out to see if .1 is available for you to take.
I was excited for a second there then realised I actually already have 12.1 and that is the version that installed last Friday.
Rats!
 

Horatio Alger

Member
Nov 20, 2020
49
40
Glasgow
My experience is very similar. 2021 LR collected 11/12, with 48.12.1 installed last week. Today's regeneration was limited at first, when it was 5 degrees. Later, it was around 10 degrees and regeneration recovered but was still less strong than it has been till now. Stopping required care to avoid overestimating regen.
 

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