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Discussion Starter · #1 ·
I wasn't quite sure how to describe this topic - which will hopefully become a thread.

I wonder whether anyone on this Forum can explain how the EQA's electric motor is controlled across the 'power spectrum' spanning providing motivation (accelerating and maintaining speed) through to modest - to significant - (non-friction brake) deceleration.

There have been many posts on the EQA and other MB-EV Forums about individuals' preferences for 'drive' settings - from D Auto, to D+ through to D- - (where available: some cars seem to only have D-). I appreciate that everyone prefers a particular setting for their own reasons. I, for instance, prefer D, especially for urban driving, because it provides mild braking when the throttle is released - and I use the paddles a lot , to provide regenerative braking wherever possible, to minimise use of the brakes and to restore some energy to the main battery.

My query is: what's happening if, say, one sets the drive to D- -? If you make that selection from say the D position (i.e. two pulls on the - paddle) whilst maintaining forward motion, you need to press harder on the accelerator (than say in D, let alone D+) to maintain speed, but if you slacken pressure on the accelerator, the car decelerates quite strongly.

Another scenario - which I encounter quite often - is descending a relatively long, steep hill in D+, with the speed limiter set. The car accelerates relatively quickly - due to gravitational force - to the speed set on the speed limiter, then you can feel the car stop accelerating as - presumably - the electric drive system applies regenerative braking due to a change in the energy flow.

Without really knowing what's happening (i.e this is central to my overall query), I assume the car has some sort of complex electronic switching device which takes account of the driver's settings (including Eco, Comfort or Sport) and other parameters such as speed limiter or cruise control settings and emergency alerts - such as from its cameras and other sensors - to either provide energy to the motor (to accelerate, or maintain speed), or draw energy from the motor (i.e. regeneration) to slow the vehicle down.

For me, this prompts at least two questions:
1. Does one's preferred drive setting (D Auto through to D- -) have any material effect on the car's long-term reliability?
For instance, is my preferred drive setting (D and constant use of the paddles) detrimental to the car's reliability (apart from possibly wearing out the paddles!), compared with say driving in D Auto, D+ or D and using the brakes more often to slow down?
2. What is the most economical drive setting? I have tried to monitor this, but without success, mainly due to the lack of a proper test environment where I can eliminate all variables apart from the drive setting.
I recently undertook a 300+ km drive in the country, during which I cruised at about 95 kph (modest speed due to range anxiety and no charging stations) in the Eco and D drive settings. I also employed cruise control for much of the journey.
I subsequently sought my dealer's advice on the best settings for such a journey and he suggested using D Auto. Presumably that would enable coasting (where the circumstances allowed it).
I also query the efficiency of cruise control, especially with route-based speed adaptation activated. The car constantly accelerates and decelerates - sometimes, quite aggressively - which I imagine would be detrimental to economy.

I am not sure whether I have articulated my query sufficiently clearly, but I hope this post initiates an interesting discussion.
 

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I am also interested. My information is that D+ is best for economy and reliability however it would be impractical to sail to a stop at junctions each time due to the length of time spent under the speed limit which is why D Auto mode switches to regen at junctions. Regarding reliability my information is that city miles affect a car more than motorways from stress on car such as from starting/stopping therefore more sailing to a stop is less stress on car. The extra economy would also create less lithium battery cycles which helps too. However again this could be impractical/illegal due to time spent not making progress while coming to a stop and gradually accelerating.

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I think you can see what the car is doing in one of the consumption menus (you can in EQC anyway). The graphic displays where power is being transferred.
 

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IMHO. It is best to use D Auto all the time. It is far easier on the mind......less thinking about things and a more relaxed journey.
 

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what's happening if, say, one sets the drive to D- -? If you make that selection from say the D position (i.e. two pulls on the - paddle) whilst maintaining forward motion, you need to press harder on the accelerator (than say in D, let alone D+) to maintain speed,
I can't say I've ever noticed that in the EQC, and I do exactly that every time I start a journey (because I mostly drive in D-- but the car defaults to D). In my experience, whenever the Power meter is in the +ve side, i.e. the motor is propelling the car forward and consuming energy, the paddle settings are irrelevant. They only come into play when the Power meter has swung -ve, i.e. the motor is actively slowing the car and generating energy. So as I start up and drive off down the road, I give two flicks on the left paddle and notice no change to anything - until I next lift my foot off.

I also query the efficiency of cruise control, especially with route-based speed adaptation activated. The car constantly accelerates and decelerates - sometimes, quite aggressively - which I imagine would be detrimental to economy.
Yes, route-based speed adaptation was the first thing I disabled.

I think the paddles are completely ignored once the cruise control is engaged. The cruise control tell the drivetrain "I want to go descend this hill at 50 km/hr (say)" and it then applies just the right amount of regen to achieve that.. regardless of how the paddles are set. The paddles are all about what happens when you lift your right foot off, but when the cruise control is engaged your right foot is resting on the carpet, so the paddle settings don't matter.

As far as coasting goes, what coasting actually means is that the Power meter is at 0. The motors are neither propelling the car, not slowing it. Electrical energy is being neither consumed nor generated. The speed of the car is then just down to gravity, gradient, rolling resistance etc.

You can actually coast in any D setting... even D--, it just take a lot more driver effort to achieve in D--. You need to monitor the Power meter, and carefully modulate your right foot to keep the Power meter at 0. Not enough right foot and the Power meter will swing -ve, too much and it will swing +ve. That's a lot of hard word and I'm not suggesting it as a viable driving technique - far easier to just select D+ and rest your right foot on the carpet. But it demonstrates there's nothing particularly complex going on with the paddles.. they just control what happens when you lift your right foot.
 

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The questions raised by the OP are exactly the sort of things I have wondered about. After the first month though I came to the conclusion Dauto gave the best efficiency primarily due to the coasting which it does a lot. At first I was concerned about the use of the friction brakes given the cars weight but with Dauto the car slows itself on approach to a junction with regen and then the last bit is friction or at least I think it is. one of my questions is whether the car chooses regen only or regen and friction when the brake pedal is pressed🤷‍♀️
Regen can never put back all the energy as there are losses which is why mercedes recommend Dauto with its coasting element. I can make one of my regular short journeys using virtually no power as once the car hits the top of the hill it just coasts home! I find the D-- odd as you seem to have to be pushing the car through resistance and it just feels you are expending more energy🤷‍♀️
I use the limiter all the time and with Dauto the car is very smooth though I notice it does take the edge off the acceleration as of course it knows you will not be passing the limit set.
My beef is that you cannot preset your preferred method and have to reset Dauto or alternatives every time. Though I can feel from the driving characteristic even as a passenger if Dauto has not been engaged it just seems to make the car more fluid.
It will be interesting to see how the friction brake pads are faring at the next service but there is dust on the wheels so they do get used……
 

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The questions raised by the OP are exactly the sort of things I have wondered about. After the first month though I came to the conclusion Dauto gave the best efficiency primarily due to the coasting which it does a lot. At first I was concerned about the use of the friction brakes given the cars weight but with Dauto the car slows itself on approach to a junction with regen and then the last bit is friction or at least I think it is. one of my questions is whether the car chooses regen only or regen and friction when the brake pedal is pressed🤷‍♀️
Regen can never put back all the energy as there are losses which is why mercedes recommend Dauto with its coasting element. I can make one of my regular short journeys using virtually no power as once the car hits the top of the hill it just coasts home! I find the D-- odd as you seem to have to be pushing the car through resistance and it just feels you are expending more energy🤷‍♀️
I use the limiter all the time and with Dauto the car is very smooth though I notice it does take the edge off the acceleration as of course it knows you will not be passing the limit set.
My beef is that you cannot preset your preferred method and have to reset Dauto or alternatives every time. Though I can feel from the driving characteristic even as a passenger if Dauto has not been engaged it just seems to make the car more fluid.
It will be interesting to see how the friction brake pads are faring at the next service but there is dust on the wheels so they do get used……
Which vehicle are you quoting? The original poster is asking about the EQA from Australia. You are driving an EQC from France and this does have different software with different electric hardware configurations, so what applies to your car (EQC) does not apply to him in his EQA. He has not quoted 4MATIC but does quote an electric motor in his post. This would point to a single axel.

The closest vehicle in terms of configuration and software to the EQA is the EQB. Even then there is a difference. I did test the UK specification EQA (single motor) and the EQB 300 (4MATIC) before purchasing. They are different animals and drive quite differently.
So to carry this forward (I did reply in the simplest terms in my previous post), I can only reply with the UK version in mind.
My car always defaults to D auto no matter what I leave it in at the end of a trip. Also, it only has 4 settings (D, D+, D-, and Dauto). Others talk about D- -, but the EQB does not have this in the UK. Not in my software configuration anyway.
As to which setting is the smoothest is very subjective and has much to do with what mode the car is in be it Sport, Comfort, or Eco. In Dauto the car is watching the traffic ahead (uses the inbuilt radar and camera) and the speed limit also the road conditions displayed on the map have an effect. So in some instances, it can slow one down quite markedly and in others not, even on the same piece of road. It can vary from one day to the next depending on traffic.
 

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Which vehicle are you quoting? The original poster is asking about the EQA from Australia. You are driving an EQC from France and this does have different software with different electric hardware configurations, so what applies to your car (EQC) does not apply to him in his EQA. He has not quoted 4MATIC but does quote an electric motor in his post. This would point to a single axel.

The closest vehicle in terms of configuration and software to the EQA is the EQB. Even then there is a difference. I did test the UK specification EQA (single motor) and the EQB 300 (4MATIC) before purchasing. They are different animals and drive quite differently.
So to carry this forward (I did reply in the simplest terms in my previous post), I can only reply with the UK version in mind.
My car always defaults to D auto no matter what I leave it in at the end of a trip. Also, it only has 4 settings (D, D+, D-, and Dauto). Others talk about D- -, but the EQB does not have this in the UK. Not in my software configuration anyway.
As to which setting is the smoothest is very subjective and has much to do with what mode the car is in be it Sport, Comfort, or Eco. In Dauto the car is watching the traffic ahead (uses the inbuilt radar and camera) and the speed limit also the road conditions displayed on the map have an effect. So in some instances, it can slow one down quite markedly and in others not, even on the same piece of road. It can vary from one day to the next depending on traffic.
The basic question raised of what is the car doing, how is it thinking about it and what actions it takes is the same whatever the drive surely?
With mine I can see when the car is just fwd, 4wd, or rwd and it switches between the options really quickly but what prompts those changes ok in the case of 4matic I have some idea but with something like the regen and dauto it is all far less clear as to which may be best for efficiency and or friction brake wear.
Interesting they seem to have made dauto the default now, the same conversation has been had for years about sport comfort individual settings in ICE mercedes.
 

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I think locale plays a bit part in the answer too. All that D-Auto and route based speed adaptation relies on quality mapping data, and in Australia the mapping data sucks. @EQA-S.oz you might want to consider disabling route based speed adaptation, it can be quite dangerous. There's a spot on the A1 somewhere south of Coffs where it will do an un-commanded harsh deceleration in otherwise clear air motorway driving - it's as if someone left a roundabout on the motorway (at least in the mapping data). MB took all of about a msec to respond with "oh yeh, you should disable route based speed adaptation", so I'm pretty sure they're aware the local mapping data isn't up to the task.
 

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Discussion Starter · #10 ·
I have found the responses to my initial post (I think Parkwood referred to it as OP) very interesting and I comment further in this post. For clarity, my car is an EQA250 (FWD), which was built in May 2021 and spent the first 3,000 km (i.e. before I bought it) as a dealer demonstration vehicle. Why did I buy a 'demonstrator' rather than a new vehicle? At the time of purchase, various EQA250 features - which I considered essential - weren't available on then-current orders and I was able to secure the vehicle immediately rather than wait a year or more for delivery. About the only thing I don't especially like is the colour (Denim). If I were to choose a colour I would probably default to white, for practical reasons, and at the time I didn't find any other colour in the range particularly attractive. Lots of greys!

I am also interested. My information is that D+ is best for economy and reliability however it would be impractical to sail to a stop at junctions each time due to the length of time spent under the speed limit which is why D Auto mode switches to regen at junctions. Regarding reliability my information is that city miles affect a car more than motorways from stress on car such as from starting/stopping therefore more sailing to a stop is less stress on car. The extra economy would also create less lithium battery cycles which helps too. However again this could be impractical/illegal due to time spent not making progress while coming to a stop and gradually accelerating.

.

I think you can see what the car is doing in one of the consumption menus (you can in EQC anyway). The graphic displays where power is being transferred.
In the city, I find D+ a bit unnerving, as the car does just "sail on" unimpeded by any sort of resistance - other than the friction brakes. It's a bit like selecting neutral in a manual transmission ICE vehicle as you approach a stopping point: no engine braking when you take your foot off the accelerator. I have a similar feeling with D Auto in the city; however, I should perhaps try it more often - especially in the country.

Regarding country v city motoring, I agree, it's generally accepted that open country running is easier on a car than stop-start city motoring. Perhaps less so for an EV? I'm not sure.

IMHO. It is best to use D Auto all the time. It is far easier on the mind......less thinking about things and a more relaxed journey.
As I commented above, I haven't found D Auto to my liking, but I'm prepared to keep trying it in various circumstances.

I can't say I've ever noticed that in the EQC, and I do exactly that every time I start a journey (because I mostly drive in D-- but the car defaults to D). In my experience, whenever the Power meter is in the +ve side, i.e. the motor is propelling the car forward and consuming energy, the paddle settings are irrelevant. They only come into play when the Power meter has swung -ve, i.e. the motor is actively slowing the car and generating energy. So as I start up and drive off down the road, I give two flicks on the left paddle and notice no change to anything - until I next lift my foot off.
In my EQA250, when I drive along a flat section of road (at urban speeds) in say D and I select D- I need to press slightly harder on the accelerator to maintain speed and press even harder if I select D- -. I understand that if you select D- or D- - immediately you take off, you would be unaware of the effect I refer to. My car also defaults to D.

Occasionally, I use my Individual setting (suspension on Sport, everything else, Comfort); I think MB could improve their EVs by allowing drive mode to be configured as part of the Individual setting, because in most cases, with consecutive starts employing the Individual setting, you can select Individual via a brief prompt on MBUX . Having said that, pulling the paddles isn't too difficult!

Yes, route-based speed adaptation was the first thing I disabled.
Subsequent to the long trip I referred to - and speaking to my dealer - I also disabled route-based speed adaptation. I haven't tried it since.

I think the paddles are completely ignored once the cruise control is engaged. The cruise control tell the drivetrain "I want to go descend this hill at 50 km/hr (say)" and it then applies just the right amount of regen to achieve that.. regardless of how the paddles are set. The paddles are all about what happens when you lift your right foot off, but when the cruise control is engaged your right foot is resting on the carpet, so the paddle settings don't matter.
Agreed, re cruise control and paddles / (D setting): cruise control is just that: in control, while set.

As far as coasting goes, what coasting actually means is that the Power meter is at 0. The motors are neither propelling the car, not slowing it. Electrical energy is being neither consumed nor generated. The speed of the car is then just down to gravity, gradient, rolling resistance etc.
I beg to disagree, dBC. As I commented earlier, in my EQA250, selecting D+ removes any decelerative effect, whereas in D I experience a mild decelerative effect when I remove my foot from the accelerator. I like that; it's very similar to most ICE vehicles. I agree, the Power meter shows 0 when you do so.

You can actually coast in any D setting... even D--, it just take a lot more driver effort to achieve in D--. You need to monitor the Power meter, and carefully modulate your right foot to keep the Power meter at 0. Not enough right foot and the Power meter will swing -ve, too much and it will swing +ve. That's a lot of hard word and I'm not suggesting it as a viable driving technique - far easier to just select D+ and rest your right foot on the carpet. But it demonstrates there's nothing particularly complex going on with the paddles.. they just control what happens when you lift your right foot.
I can't 'coast' in my car when drive is set to D, D-, or D- -, but I can achieve a Power meter reading of 0 by adjusting my foot pressure on the accelerator.

I think we're in agreement as far as the effect of the paddles is concerned. D+ provides no regenerative braking when you lift off and the settings D through to D- - provide progressively more regenerative effect as you move through that sequence, but the regenerative effect can be nullified by applying pressure to the accelerator - to the point of creating an accelerative effect, dependant on the pressure on the accelerator. D Auto does all of the above via the vehicle's sensors and 'brain'. Some people like D Auto, others are wary of it, or dislike it.

The questions raised by the OP are exactly the sort of things I have wondered about. After the first month though I came to the conclusion Dauto gave the best efficiency primarily due to the coasting which it does a lot. At first I was concerned about the use of the friction brakes given the cars weight but with Dauto the car slows itself on approach to a junction with regen and then the last bit is friction or at least I think it is. one of my questions is whether the car chooses regen only or regen and friction when the brake pedal is pressed🤷‍♀️
I'm encouraged by your positive comments about D Auto. If I remember correctly, your EV is an EQC. Perhaps there's some difference in the calibration of D Auto as between the EQC and the EQA250.

Two interesting questions: whether the car uses regen alone to decelerate, or regen plus friction brakes. Perhaps it depends on the circumstances; however, when I've contemplated this I've also considered the amount of retardation taking place and in most cases I feel it's within the capability of the regeneration system (alone); i.e. similar to D-, or in some cases, D- - (e.g. when descending a steep hill (in D+), with the Speed Limiter set).

Secondly, does your EQC come to a complete halt with D Auto selected? As I've said, my experience with D Auto is minimal, but with say D- - selected, the car slows appreciably as it approaches another vehicle at say a set of traffic lights, but I always need to apply the friction brakes for the final bit of retardation.

Regen can never put back all the energy as there are losses which is why mercedes recommend Dauto with its coasting element. I can make one of my regular short journeys using virtually no power as once the car hits the top of the hill it just coasts home! I find the D-- odd as you seem to have to be pushing the car through resistance and it just feels you are expending more energy🤷‍♀️
Agreed, in all respects, noting MB's 'recommendation' re D Auto.

I use the limiter all the time and with Dauto the car is very smooth though I notice it does take the edge off the acceleration as of course it knows you will not be passing the limit set.
My beef is that you cannot preset your preferred method and have to reset Dauto or alternatives every time. Though I can feel from the driving characteristic even as a passenger if Dauto has not been engaged it just seems to make the car more fluid.
It will be interesting to see how the friction brake pads are faring at the next service but there is dust on the wheels so they do get used……
I use the Speed Limiter almost all the time and I think it also 'takes the edge off acceleration' in the other drive modes (at least D to D- -, which I use); I guess it's a somewhat pre-emptive action.

My beef is that you cannot preset your preferred method and have to reset Dauto or alternatives every time. Though I can feel from the driving characteristic even as a passenger if Dauto has not been engaged it just seems to make the car more fluid.
It will be interesting to see how the friction brake pads are faring at the next service but there is dust on the wheels so they do get used……
As I commented above, I think MB should consider making the drive mode part of the Individual configuration - even if your Individual setting was Comfort for everything, but say D Auto for drive mode (assuming D is the default). I don't think it would compromise safety, as the driver would have to consciously select Individual.

Yes, brake pad (and disc) wear: I try to minimise it.

Which vehicle are you quoting? The original poster is asking about the EQA from Australia. You are driving an EQC from France and this does have different software with different electric hardware configurations, so what applies to your car (EQC) does not apply to him in his EQA. He has not quoted 4MATIC but does quote an electric motor in his post. This would point to a single axel.
My apologies for not clarifying my car's spec: now addressed (above).

No doubt the "hardware" configuration does affect software configuration. It would be interesting to know to what extent and also whether MB tweaks the configuration according to the country (or broad region) of sale. I suspect not; it would add enormous complexity to an already complex system and portfolio of vehicles.

The closest vehicle in terms of configuration and software to the EQA is the EQB. Even then there is a difference. I did test the UK specification EQA (single motor) and the EQB 300 (4MATIC) before purchasing. They are different animals and drive quite differently.
So to carry this forward (I did reply in the simplest terms in my previous post), I can only reply with the UK version in mind.
My car always defaults to D auto no matter what I leave it in at the end of a trip. Also, it only has 4 settings (D, D+, D-, and Dauto). Others talk about D- -, but the EQB does not have this in the UK. Not in my software configuration anyway.
As to which setting is the smoothest is very subjective and has much to do with what mode the car is in be it Sport, Comfort, or Eco. In Dauto the car is watching the traffic ahead (uses the inbuilt radar and camera) and the speed limit also the road conditions displayed on the map have an effect. So in some instances, it can slow one down quite markedly and in others not, even on the same piece of road. It can vary from one day to the next depending on traffic.
Interesting that your EQB defaults to D Auto. I wonder whether MB has changed the default drive setting across the range?

I think I've read elsewhere that MB discontinued D- - in later EQA builds than mine. I must say that I like D- - as it definitely provides more retardation than D-. Perhaps they've reconfigured D- so that it's now slightly more aggressive?

Interesting comments on the behaviour of D Auto. Is it very clever or too clever?!

The basic question raised of what is the car doing, how is it thinking about it and what actions it takes is the same whatever the drive surely?
With mine I can see when the car is just fwd, 4wd, or rwd and it switches between the options really quickly but what prompts those changes ok in the case of 4matic I have some idea but with something like the regen and dauto it is all far less clear as to which may be best for efficiency and or friction brake wear.
Interesting they seem to have made dauto the default now, the same conversation has been had for years about sport comfort individual settings in ICE mercedes.
It would be interesting to have some insight to MB's R&D testing, as one assumes they did a lot of work before adopting specific configurations for their wide range of vehicles. And, no doubt, changes continue to be made on the basis of owners' experiences in various circumstances and regions globally.

I think locale plays a bit part in the answer too. All that D-Auto and route based speed adaptation relies on quality mapping data, and in Australia the mapping data sucks. @EQA-S.oz you might want to consider disabling route based speed adaptation, it can be quite dangerous. There's a spot on the A1 somewhere south of Coffs where it will do an un-commanded harsh deceleration in otherwise clear air motorway driving - it's as if someone left a roundabout on the motorway (at least in the mapping data). MB took all of about a msec to respond with "oh yeh, you should disable route based speed adaptation", so I'm pretty sure they're aware the local mapping data isn't up to the task.
Yes, my EQA250 does have mapping with quite a bit of information, but Australia is a big, largely uninhabited country and to map every metre of every road would be nigh on impossible. I certainly found with cruise control and route-based speed adaptation enabled, the car negotiated some corners with an element of exuberance, whilst the 'nannys' were very much in evidence in other places. Not ideal.

So in some instances, it can slow one down quite markedly and in others not, even on the same piece of road. +1
Mmmm!
 

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In my EQA250, when I drive along a flat section of road (at urban speeds) in say D and I select D- I need to press slightly harder on the accelerator to maintain speed and press even harder if I select D- -
I did test that in my EQC400 yesterday and wasn't able to replicate it. I'm hours away from launching on a 200km motorway trip, so should have plenty of opportunity to reconfirm.

I beg to disagree, dBC. As I commented earlier, in my EQA250, selecting D+ removes any decelerative effect, whereas in D I experience a mild decelerative effect when I remove my foot from the accelerator. I like that; it's very similar to most ICE vehicles. I agree, the Power meter shows 0 when you do so.
I think we're actually in agreement even there. I potentially threw you by my weird definition of "coasting". I think of "coasting" as having the car moving, while the power meter reads 0. That's achievable in any D setting (it's just really hard to do in the lower D settings).

I can't 'coast' in my car when drive is set to D, D-, or D- -, but I can achieve a Power meter reading of 0 by adjusting my foot pressure on the accelerator.
Yes, that's all I was trying to say. I call that "coasting". I think your definition of "coasting" means you're not having to do anything with your foot. From a driver's point of view your definition makes more sense, my definition is more looking at things from an efficiency point of view. I guess what I was trying to say is there are plenty of ways making the car move "for free". Unlike in an ICE car, it's the Power meter that tells you whether the car is moving freely or not - not the position of your right foot.

Two interesting questions: whether the car uses regen alone to decelerate, or regen plus friction brakes. Perhaps it depends on the circumstances; however, when I've contemplated this I've also considered the amount of retardation taking place and in most cases I feel it's within the capability of the regeneration system (alone); i.e. similar to D-, or in some cases, D- -
Have you configured your instrument cluster to include the Power meter, if only while contemplating these questions? I find it very informative. I live at the top of a very steep hill (too steep to ride my e-bike up). When I back off completely in D-- the Power meter swings to -80% and it's really holding things back. Eventually I get to spot where I need even more slowing so gently touch the brake pedal.. that causes the Power meter to swing to -100% and things really slow down. I'm yet to find any brake dust on my front wheels even though that happens pretty much at the start of every journey. BTW, I think this is one aspect where the behaviour will vary a lot from model to model. Coming down that hill, even at -80% my Energy Flow screen is showing both motors are involved in the "braking". I'm certain different models will have different max-regen capabilities... probably somewhat correlated to how much power they have. I've got 300kW of power, you've got 140kW, so I imagine mine can do a lot more regen braking than yours - but mine is also quite a bit heavier than yours, so it all gets a bit blurred. Battery capacity and max DC charging rate might be relevant too.

Yes, my EQA250 does have mapping with quite a bit of information
My anecdote about the unexpected hard deceleration on a clear motorway wasn't from my EQC (which has even older mapping data than your EQA). It was from an EQS AMG 53 delivered new just two months ago. Presumably that has the best mapping data MBA can find, and yet still they told him to turn it off.

I'm encouraged by your positive comments about D Auto.
I don't want to rain on your parade, but I think all the folk that like D-Auto live in Europe. That same mapping data that is making route guided speed adaption unusable in Australia will also be heavily involved in D-Auto calculations. My mate with the EQS tried it and lasted all of about 5 mins. He's sticking with D and I'm sticking with D-- in my EQC. Nice that we all have the choice to tailor our rides.
 

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In my EQA250, when I drive along a flat section of road (at urban speeds) in say D and I select D- I need to press slightly harder on the accelerator to maintain speed and press even harder if I select D- -
OK, with plenty of flat motorway to test on, I had cruise control and speed limiter off, Speedo reading a steady 100 km/hr, Power meter was reading +8%, paddles were set to D and I kept my right foot locked in the one position. I then went to town on the paddles... D-, D--, D, and D+.... nothing changed... speed stayed constant and so did the Power meter. So I think we can conclude that's a definite difference between the EQC and EQA - unless maybe it's speed related, you at urban speeds and me at motorway speeds.

Somewhat related to the topic, I'd charged the car to 100% for this trip, which I rarely do, and noticed a difference heading down my hill. I backed off completely at the usual location and the Power meter only swung to -40% (compared to -80% as described above) which gave much less "braking", then when I pressed the brake pedal it just stayed at -40%, and the pedal felt quite different. So I think for the first time ever I've used my friction brakes coming down my hill. So another criteria for how much re-gen braking you get is how much headroom the battery has to accept more energy. If the battery is at 100%, you get reduced re-gen.
 

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Discussion Starter · #13 ·
Thank you for your detailed responses to my last post, dBC.

Post #12: Interesting insight to your 'going to town on the paddles' experience. Maybe the EQC400 and EQA250 do differ in regard to the effect of the drive setting; perhaps with the more powerful and heavier EQC the change in setting is less apparent. Also, as you say, momentum may be a factor.

I was particularly interested in your regen braking experience, having charged the EQC400 to 100%. The possibility that regenerative braking capability is reduced when the battery is at, or near energy capacity seems logical to me. Maybe another reason to limit recharging to 80%, unless you need more range for a specific journey?

Yesterday, I did several suburban trips and on several occasions tried D Auto. I'm still not a fan of that drive setting in an urban environment. Perhaps, as you suggest, dBC, it's a setting better suited to the European environment with their enhanced mapping support (assuming D Auto relies partly on GPS data). Having said that, I'll certainly try it next time I travel in the country. In urban areas, however, I feel more comfortable using D and the paddles. Some people prefer full automation; I quite enjoy some manual input - and my instrument panel is always configured with the Power meter in the right hand dial position. It is nice to be able to select one's individual preference, whatever that may be. Although, given my constant use of the paddles, I wish my HUD included the capability to display the drive setting.
 

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perhaps with the more powerful and heavier EQC the change in setting is less apparent. Also, as you say, momentum may be a factor.
Just to be clear, the different paddle settings in the EQC are noticeably (even vastly) different so long as the Power meter is in the -ve. I don't think it's just a subtlety thing that I'm missing when the Power meter is in the +ve, I think they're truly ignored when the Power meter is +ve. TBH that's also kinda' how I'd expect it to work - given they are the re-gen settings I wouldn't expect them to affect anything when you're not re-gen'ing. I can't imagine what is going on inside the EQA to cause the behaviour you're observing.
 

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Discussion Starter · #15 ·
I can't imagine what is going on inside the EQA to cause the behaviour you're observing.
I'm not sure either, not that it bothers me. For quite a while, I adopted a practice a bit like yours, dBC; I selected D- as soon as I began a journey and left it there. I enjoyed the immediate braking effect as I released pressure on the accelerator. I contrast that with D+, where the car sails merrily on. It gives a perception of energy efficiency, but retardation requires either a couple of quick pulls on the left paddle, or application of the friction brakes, or both. For me, the lack of retardation on accelerator lift-off outweighs any energy efficiency benefit. Although, as I've said before, I'm keen to try D Auto on a long journey.

Coincidentally, I read an article yesterday which I found interesting in the context of my EQA250's retardation effect. It is a progress report by Wheels magazine's former editor, Alex Inwood on his experience with a long-term road test of a current Mitsubishi Outlander PHEV. I quote:

"One thing I have been doing to extend the battery charge is playing around with regen braking. Mitsubishi says the regen on this generation PHEV is twice as strong as the model it replaces, and there are six different levels of intensity to choose from. You cycle through them by using the shift paddles on the steering wheel - left for more regen, right for less - and it's surprisingly fun to use on the fly. ............. Unlike the other five modes, the strongest setting is actually far less intuitive to use and even on a constant throttle you can feel the regen at work, as though your passenger has just eased on the handbrake. ........."

Easing on the handbrake is a good analogy to the feeling in my EQA when, driving on a constant throttle (in D), I select D-, or D- -.

I think I've said enough about that, but I was interested to read about Alex Inwood's experience in the Outlander. By the way, this issue (of Wheels) is the 2022 Yearbook and it includes a comprehensive review of sub-$100K EVs. It includes the EQA and the EQB, neither of which particularly excite the journalists. I did agree with them on one point though: that Merc's adaptive suspension - in my EQA, at least - would benefit from a setting between Comfort and Sport.
 

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It gives a perception of energy efficiency, but retardation requires either a couple of quick pulls on the left paddle, or application of the friction brakes, or both.
Do you mean application of the friction brakes, or do you man application of the brake pedal? In most EVs (but notably not Teslas) application of the brake pedal just increases re-gen braking - you should be able to see that on the Power meter. Further application of the brake pedal will invoke the friction brakes but at least on my EQC you can kinda' feel that transition as the pedal feels different once the real friction brakes get involved with the slowing down process. So applying the brake pedal mightn't be as bad for efficiency as you think.

In my EQC experiments, I've not noticed any significant difference in efficiency using the different D settings. Ultimately the same amount of re-gen braking happens, I just have to do different things with my feet to make it happen.
 

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Discussion Starter · #17 ·
dBC, I am not sure that I have identified the correct "Power meter" you refer to. Does it look like the first image attached, or the second, or is it something different? I always drive with the second image meter displayed and monitor the energy used on a given journey. However, in my EQA250, that meter doesn't actively display regeneration, it only shows the amount of energy being used and during regeneration it shows 0, but the amount of energy consumed during the journey usually drops a little, reflecting regenerated energy
Speedometer Gauge Font Trip computer Odometer
Speedometer Odometer Vehicle Gauge Trip computer
.
 

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The first one is the one you want.... it'll swing clockwise from 0 when you're consuming energy and anticlockwise from 0 when you're re-gening.

If you select D+ for example, and take your foot off the accelerator completely you'll see it drop to 0. If you then touch the brake pedal you'll see it swing negative to indicate that the brake pedal has invoked re-gen braking for you.

If you do the same in D, it'll go slightly negative when you take your foot off the accelerator, showing you there's a little re-gen going on. If you touch the brake pedal it'll swing further negative.

Ditto for D- and D--.
 

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No worries, hopefully you'll find it informative. If you want to go all out, you can also select the "Progressive" instrument cluster style. I'm not a big fan of that style, but for the purpose of these experiments it has the advantage of actually giving you a numeric readout on the Power. That's how I was able to quote the +8% above.
Car Automotive design Speedometer Personal luxury car Gauge
 
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