Unintended/Over Acceleration Event

[Hota]

Something that freaked me out a bit happened earlier today so I thought I'd share. I've already reported it to Tesla and they've escalated and are pulling the logs.

I hopped into my Model 3 to head home from work, stepped on the brake and shifted the car into D to pull forward out of the parking spot (I backed in).

As I gently applied the accelerator pedal to ease forward (and turn left) out of the parking space to head down the parking aisle, the car moved forward much faster than expected so I let off the pedal. I try again and the car lurches forward pretty quickly as if I mashed the pedal about halfway down. Letting go of the accelerator pedal doesn't seem to kick in regenerative braking so I press on the brake to slow the car down to a speed appropriate for a parking lot.

After hitting the brake, the problem never reappeared.

It's almost as if the "throttle map" was messed up for a few seconds asking the car to deliver much higher current than it should have at a 5-10% pedal position.

Very odd and a bit freaky.

 

[S4WRXTTCS]

This is the first time I've read an unintended/over acceleration event where I had a strong inclination to believe the story.

I did find my Model 3 accelerator a bit more touchy than my 70D

The first time kinda startled me a bit. But, nothing like this.

 

[Dr. J]

Letting go of the accelerator pedal doesn't seem to kick in regenerative braking

What was the approximate state of charge of your battery? I ask because regen is said not to work over about 93% SOC.

 

[Az_Rael]

Very strange. I have had my 3 do some very weird stuff, but l luckily nothing critical drive function related. Mine is often VERY slow to wake and sometimes it will let me shift into drive while the screen is still black. I notice when that happens that I don't have creep anymore which is normally turned on for my profile. I assume you had full screen functionality in this case though.

 

[Hota]

What was the approximate state of charge of your battery? I ask because regen is said not to work over about 93% SOC.

SOC was at about 90%. To be honest, I'm not 100% sure regen wasn't working. I just noticed I was going pretty fast for a parking lot and I wasn't slowing down fast enough when I took my foot off the accelerator pedal.

 

[Hota]

Very strange. I have had my 3 do some very weird stuff, but l luckily nothing critical drive function related. Mine is often VERY slow to wake and sometimes it will let me shift into drive while the screen is still black. I notice when that happens that I don't have creep anymore which is normally turned on for my profile. I assume you had full screen functionality in this case though.

Full screen was working but I noticed that my radio streaming favorites were missing (typical). I did notice earlier in the previous drive that the owner's manual wasn't really working.

 

[S4WRXTTCS]

What was the approximate state of charge of your battery? I ask because regen is said not to work over about 93% SOC.

I think it's more likely temperature related.

This time of year is kinda of a sucky time for EV owners because we start to realize how much we grew to love re-gen during the summer, and now it's slipping away.

 

[fr100]

Creep on or off?

 

[ba2002]

I'm only a couple hundred miles into my P3D, but just today commuting home from work I thought to myself the P3D is much trickier to smoothly modulate the acceleration/deceleration than my P90D was. Maybe it's just due to stronger regen in the 3 and the fact one of the motors is different and I'll get use to it over time. But I did wonder if the throttle mapping is a little more aggressive.

 

[Dr. J]

I think it's more likely temperature related.

This time of year is kinda of a sucky time for EV owners because we start to realize how much we grew to love re-gen during the summer, and now it's slipping away.

Educate me on the regen-temperature relationship. Please!

 

[Daniel in SD]

The first and only time I charged to more than 90% I was quite startled by the lack of regen. You really get used to it.

 

[AnesDragon]

When I charged to 100% just to make sure the batteries full capability, I got a notice that the regenerative brake would not function optimally because of the battery charge status. When I drove, I definitely noticed the difference even though I've only had my Tesla only a few days. I definitely love regenerative braking!

 

[S4WRXTTCS]

Educate me on the regen-temperature relationship. Please!

When the battery is cold it can't take as big of a charge.

Re-Gen is charging the battery, and it can actually be a pretty significant amount of current. Most re-gen events are large amount of current for a short amount of time. That's what most braking is.

In the dead of winter it might take hardly any charge at all when it's cold. So you'll be driving to work with hardly any re-gen, but you'll notice it increasing as the battery warms up. Usually by the time I've gotten to work the car is no longer limited re-gen.

With my Model S it was fairly surprising in that it didn't really need to be that cold out before it started to limit regen. The Model S displayed this really clearly, and it was easy to see where the limit was. With the Model 3 it seems way less user friendly in the display of it.

I haven't had the Model 3 long enough to see when the re-gen starts to get limited. Like right now its 49F, and I fully expect that I'll have slightly limited re-gen when I start my drive home.

 

[scottf200]

Something that freaked me out a bit happened earlier today so I thought I'd share. I've already reported it to Tesla and they've escalated and are pulling the logs.
I hopped into my Model 3 to head home from work, stepped on the brake and shifted the car into D to pull forward out of the parking spot (I backed in).
As I gently applied the accelerator pedal to ease forward (and turn left) out of the parking space to head down the parking aisle, the car moved forward much faster than expected so I let off the pedal. I try again and the car lurches forward pretty quickly as if I mashed the pedal about halfway down. Letting go of the accelerator pedal doesn't seem to kick in regenerative braking so I press on the brake to slow the car down to a speed appropriate for a parking lot.
After hitting the brake, the problem never reappeared.
It's almost as if the "throttle map" was messed up for a few seconds asking the car to deliver much higher current than it should have at a 5-10% pedal position.
Very odd and a bit freaky.

Sorry to hear that. I see this saftey feature below include in v9 but others said it existed before. -- V9's obstacle aware acceleration is already present in 2018.34.1 (current V8.1 software) : teslamotors

Obstacle-Aware Acceleration - All cars
Acceleration is automatically limited if an obstacle is detected in front of your vehicle while driving at low speeds. Obstacle-Aware Acceleration can be enabled or disabled in Controls > Autopilot.

 

[Hota]

Creep on or off?

Creep off.

FYI - I haven't owned a car that "creeped" in almost 20 years.

 

[Hota]

Sorry to hear that. I see this saftey feature below include in v9 but others said it existed before. -- V9's obstacle aware acceleration is already present in 2018.34.1 (current V8.1 software) : teslamotors

Obstacle-Aware Acceleration - All cars
Acceleration is automatically limited if an obstacle is detected in front of your vehicle while driving at low speeds. Obstacle-Aware Acceleration can be enabled or disabled in Controls > Autopilot.

What happened to me was opposite of this. It wasn't limiting my accelerating but rather accelerated a lot more than I had inputted into the accelerator pedal.

 

[Hota]

Maybe it's just due to stronger regen in the 3 and the fact one of the motors is different and I'll get use to it over time. But I did wonder if the throttle mapping is a little more aggressive.

I switch between my Model S and Model 3 quite a bit (both non P) and the throttle mapping isn't that much different - although the 3 slows much faster with regen (lighter weight?). I have over a 1000 miles on my 3 so I'm pretty comfortable with it. I don't use creep and am able to modulate the car within an inch of my desired spot in my garage every day.

What I experienced was that the throttle mapping was just "off" for a few seconds before I jammed on the brakes.

 

[thecloud]

One possibility I haven't seen mentioned yet: if you previously had your cruise control set to something high (say, 70 mph) and then unintentionally activated it when driving at a much slower speed, the sudden lurch forward as it tried to accelerate to the set point would certainly be disconcerting. And of course, hitting the brake would cancel it, just as described in the first post.

I had this happen when I was first getting used to the Model S cruise control, so I wonder if this is also happening to other people.

 

[Hota]

One possibility I haven't seen mentioned yet: if you previously had your cruise control set to something high (say, 70 mph) and then unintentionally activated it when driving at a much slower speed, the sudden lurch forward as it tried to accelerate to the set point would certainly be disconcerting. And of course, hitting the brake would cancel it, just as described in the first post.

I had this happen when I was first getting used to the Model S cruise control, so I wonder if this is also happening to other people.

Perhaps...but from my recollection, the vehicle stopped accelerating the first time I let go of the accelerator pedal and then the same thing happened again the second time I pressed the accelerator. Hopefully Tesla will get back with me and tell me if ACC was activated by accident.

 

[SMAlset]

Apart from regen limited when near full charge (no where for regen to put power back in the battery), those new to their car should also be aware with winter coming up that once the temp starts dropping, you will wake up to find that it takes a while for the battery to warm up and allow for regen. On our Model S you could visually see this by the graph going yellow. Not sure how Model 3 handles this on any display/s. I really need to sit down with the manual for a while.