Anybody have an brake-related accident in an i3?

[saigopisetty]

We have been driving short distances daily to drop kids and for groceries once in two/three weeks. Any suggesting on bringing this to BMW notice?

 

[jadnashuanh]

I have not been that impressed by the brakes on my i3.
In an emergency, they seemed to lack the bite I expected. I assumed that the weight of the car and the narrow tyres are contributing factors.

Braking is a function of the tire footprint and the reason BMW went with the larger, narrow tire for the i3 is that it has less drag while moving, but can retain the same footprint as a smaller diameter, wider tire. Total footprint is a function of the vehicle weight and tire pressure. The wheel size will play a part in the shape of the footprint, but not the total size. On the wheel/tire combo in the i3, it is a longer one than wide, versus maybe a square or oriented width-wise you'd get with a smaller wheel. In reality, that might help in traction going straight for either starting or stopping, depending on the tread, and less for cornering.

Because we rely more on regen to slow us down, the brakes don't get used that often. They can develop a coating of rust, but also, if there's much of any gunk that got onto them, it doesn't get worn/scraped away like on a vehicle where the brakes are used constantly. That could affect the end result of your braking force.

The i3 still has a conventional hydraulic master cylinder, so the brakes should work even without power. The ABS unit can play into that if traction is reduced and it detects a wheel slipping, though.

 

[jadnashuanh]

We have been driving short distances daily to drop kids and for groceries once in two/three weeks. Any suggesting on bringing this to BMW notice?

BMW will take notice if you file a complaint to the NHTSA. You can do that electronically on their website to report a problem.

Before I did that, though, I'd have a BMW shop take a look to verify that they see nothing wrong, and that any already discovered software glitch might need to be applied.

 

[hollyakala]

I just got into an accident in my 2016 i3 as I was starting to accelerate on a highway on-ramp.

After the initial curve of the road, I was surprised by the traffic meter light. A car was already waiting for the light to change from red to green, and I hit the brakes.

I hit the brakes really hard and they engaged but did not prevent my hitting the car. I get it, the distance was too short. But the car began to accelerate again, kept hitting the car in front of me, such that I had to keep hitting the brakes. It happened really quickly and there were no witnesses that could describe exactly what happened. Perhaps my car got caught on the fender of the Range Rover ahead of me. The airbags did not deploy.

The entire front panel/hood of the car was compacted and forced a crack in the windshield. The driver's side door was difficult to open, and the hood was sealed shut. The auto body shop is estimating repair costs near the sale value of the vehicle such that it will likely be totaled. I don't think I will replace my car with an i3 again, especially when I'm already having issues with the short driving range.

I am very disappointed that the brakes did not stop the car completely. Also, all parties have chiropractor appointments to deal with the multiple hits.

 

[user 7492]

I bought a used 2018 i3 from Green Eyed Motors in Boulder Colorado about seven months ago. I have worked on cars for many years and this car was in excellent mechanical condition with low (~18k) miles. They got the car as a lease return from BMW financial services.

Seven days after purchasing it, I was involved in an accident where there was some construction in the left lane of a two lane arterial with weekend shopper traffic. We were all going about 15mph to merge together and suddenly the entire line of cars put on their brakes. I was new to the car and know to put my foot hard on the brakes on an ABS car. Let the ABS figure out the right amount to do in order to stop the car, then modulate the brakes by backing off when there is safe following distance and time for the brain to catch up.

Unfortunately in this situation, the brake pedal went to the floor and there was clearly no stopping power except that of the regenerative system. If I had known this was about to happen, I had room to steer the car into the ditch and only affect my car. Instead, it ran right into the back of the car in front of me. The bill on the i3 was in the tens of thousands, the car in front of me had rear end damage as well.

I took the car to Gephardt BMW in Boulder and they went through it and said there was nothing wrong with it. The tech took me out for a drive and carefully put his foot on the brake to demonstrate how the ABS does it's job from 30+ MPH. As soon as I took the wheel back at the shop parking lot, I brought it up to 15MPH and stomped on the brakes. Same issue, the car kept rolling forward.

I bet I could reproduce it with any i3, but I was already committed to this car and who is going to believe you that "the brakes didn't work". Any time I tell the story, I get the eyeroll.

If anyone wants my contact information in a class action lawsuit, DM me. My insurance premiums have doubled and I lost $8,000 returning a car that I no longer trusted to the dealer after it was fixed. I think the insurance company deserves to see the truth as well so they can reconcile what happened.

 

[Pahaska]

I have had the same sort of hard stops in two different I3s (2017, 2019). The brakes worked perfectly in every instance.

 

[Anonymous]

I just tried this in my 2015 - 15 mph and hard brake. Car stopped instantly.

Was the road wet? Gravel? The ABS keeps the wheels from locking up - if you were on a slippery or loose surface and slammed on the brakes, the ABS might allow some travel - but less than without ABS, because then you'd just be skidding on the slippery or loose surface with the wheels locked.

If not, a guess would be that when the brakes were flushed last, they botched the job and there is some air in the brake lines, or they weren't flushed at all, fluid was low enough that air got into the lines, and someone just topped up the fluid without flushing the lines. Because that statement you made "the brake pedal went to the floor and there was clearly no stopping power" is classic brake failure due to air in the brake lines.

Think about it - if i3s failed to brake at low speed during a panic stop, these boards would be so full of accident reports there would be no room for anything else, and the NTSB would be mandating a recall. I doubt there is an i3 owner in existance who hasn't had to slam on the brakes in traffic for accident avoidance.

 

[agzand]

I think it is a good idea to implement a brake clean up cycle for EVs with strong regeneration (somehow similar to REX maintenance cycle). The car should detect brakes have not been used for a few weeks and disables regeneration for a few braking cycles to clean up the rotors.

I had a relatively hard stop a couple of weeks ago, I felt there was a split second of hesitation but once I pushed the pedal hard the car stopped instantly. When you have such a strong regeneration the brakes will feel different than an ICE car, you need to get used to it.

 

[LiamPullman]

Even at low speeds, the car doesn't use regenerative brakes alone, but they can get covered in sleek over time. But it is very common for the brakes' effectiveness to alter over time on electric and hybrid cars if they are not taken to the highway from time to time. Actually, I had such an incident with a hybrid Toyota. The speed wasn't exaggerated, around 60 mph, but I still failed to break in time, and the car's collision prevention also couldn't help. So, with the help of https://www.4injured.com I persuaded the insurance agency.

 

[Ava3i3]

I recently had a similar issue in my 2016 i3. I pulled to the curb and thought I put in park. Then my car started to roll. When I went to brake it kept going and I ended up hitting the parked car in front of me. I couldn’t understand what happened so I assumed I must have touched the accelerator too. Speaking of which, does anyone know a good auto body place that specializes in i3 in Los Angeles?

 

[alohart]

I recently had a similar issue in my 2016 i3. I pulled to the curb and thought I put in park. Then my car started to roll.

This is why it's important to develop the habit of first applying the parking brake with the brake pedal depressed (switch on the center console) before shifting to Park. The parking brake will prevent rolling as well as eliminating stress on the parking pall when parking on an incline without the parking brake on.

 

[AUTOMAN]

Interesting to read these posts having replaced many brake pads over the years there is a definite difference in the quality of various brake pads and the result is good or poor performance .Being a moderate driver I often find I rarely have to use the brakes due to the action of the recharging on the over run . However I do make a point of applying the brakes to remove the slight buildup of corrosion on the disc . With regards to the servicing of the brakes and brake fluid,the fluid is hydroscopic ( absorbing water from the atmosphere) which results in having to replace the fluid at service intervals.
I have a relatively cheap tester which indicates how much moisture is in the fluid my i3 indicates virtually none .I suspect this is due to not having to use the brakes and the fact the brakes do not get hot and boil the fluid. It is still good to replace the fluid at the correct service intervals.

 

[UpNorth]

I find the brakes on my Tesla Model 3 have much more bite and stopping power than my BMW i3s.

This surprised me as a new i3 owner. So much so that I have had a couple of incidents where the stopping distance has caught me out a few times.

It’s on my list of things to asked to be checked at my next service.

 

[RicardoF1RST]

1. When above 97.5% my i3s uses the brakes rather than regeneration (the fronts slow the car as well as the rears)
2. I believe the "regeneration meter" is actually indicating deceleration level
3. The i3's brakes can be cooked just like any cars brakes - try doing 3 emergency stops from 100mph, actually be careful on the 3rd
4. The i3 was built to be light, so it has very small discs (rotors) and small callipers - the brakes are OK, but not great
5. Drive accordingly

 

[tob1as]

I find the brakes on my Tesla Model 3 have much more bite and stopping power than my BMW i3s.

This surprised me as a new i3 owner. So much so that I have had a couple of incidents where the stopping distance has caught me out a few times.

It’s on my list of things to asked to be checked at my next service.

However, in reality, per testing data, the BMW i3 only travels 108 feet from 60 mph to a stop vs the model 3 taking 133 feet.
So, while the Model 3 might feel more solid under breaking, it takes longer to stop. I think the feel may have to do with how much lighter the i3 is, and those small contact patch tires more quickly triggering ABS.

 

[ksnax]

Braking performance is also affected by suspension setup. Having a shorter wheelbase and a more firm ride, the i3 is more sensitive to sudden jabs at the brakes, engaging the ABS faster. So while it may stop faster than the Model 3, it will feel unsettled more quickly as the ABS jumps in.

I find the brakes to be more than adequate for normal driving and exceptional when deliberately threshold braked, but the ABS is a lackluster budget minded setup with only 2 hydraulic circuits on a diagonal split between the front and rear, and even becomes a detriment during evasive maneuvers. So while it does a great job under straight braking, make a turn while asking for maximum grip and it falls apart catastrophically if there are any bumps. (The tire with the least traction, inside rear, loses grip, forcing the system to cycle the front outside tire, which has the most grip and probably is not skidding.)

I've removed 2-channel split systems on other cars because they were just that bad. (Simply disabling them really doesn't work.) But those were race cars, not my daily drive.

 

[Royahoy]

I recently had a similar issue in my 2016 i3. I pulled to the curb and thought I put in park. Then my car started to roll. When I went to brake it kept going and I ended up hitting the parked car in front of me. I couldn’t understand what happened so I assumed I must have touched the accelerator too. Speaking of which, does anyone know a good auto body place that specializes in i3 in Los Angeles?

I recently had a similar issue in my 2016 i3. I pulled to the curb and thought I put in park. Then my car started to roll. When I went to brake it kept going and I ended up hitting the parked car in front of me. I couldn’t understand what happened so I assumed I must have touched the accelerator too. Speaking of which, does anyone know a good auto body place that specializes in i3 in Los Angeles?

I'm 6'4" with big feet. I find that in a traffic queue it is easy to catch the accelerator pedal with the side of my shoe when pressing the brake. With the i3 the top of the accelerator pedal is level with or even higher than the brake, unlike other cars I have had. Coupled with the insane amount of torque the harder I press the brake the more the motor drives and there is no time to readjust my foot. Bang! It's fly by wire so WHY don't bmw inhibit the accelerator when the brake pedal is pressed?