I was driving uphill on a winding, narrow highway, California State Route 18, when the range extender kicked in and I had a sudden loss of power. I could not maintain vehicle speed. It was terrifying. I was alone. I didn't know what to do. I turned on my hazard lights and I pulled over every time vehicles came up behind me.

- Los Angeles, CA, USA

The adaptive cruise control (acc) in the I3 is single camera based, and will deactivate during a number of conditions (such as driving into direct sunlight which blinds the camera.) this is a design limitation, but not the problem. The problem is when acc deactivates, the car immediately goes into full regen braking without warning. At highway speeds this is a sudden and significant deceleration that poses a safety hazard (being rear ended).

- Santa Clara, CA, USA

The cruise control randomly turns itself off and the car immediately goes into regenerative braking. The service technician was unable to duplicate the problem and no repairs were performed by the dealer. It has happened under many different driving conditions, and different times of the day and night on freeways and back roads.

- Hueytown, AL, USA

Our car would not make it up the hill during a rainstorm on the highway in camarillo, ca. It went from 65 down to 45. It happened to us twice on this trip. We were using the range extender. We have videos the vehicle losing power.

- Valley Village, CA, USA

The acc (active cruise control) surprisingly stops working when facing a bright sun. This happens often, but it took me a while to understand what was happening. It is very dangerous at high speeds if someone is behind me. When the sun hits the camera, the acc shuts down (with a warning on the screen) and the regen braking system kicks in causing the car to slow down much more than coasting. I have been told that the brake lights go on, but if a car is following and traffic conditions do not suggest that our car should be braking, the car could rear end us. The I3 only has a camera to run the acc. In other cars, there are both cameras and radar. Our 2011 mkx has an intelligent cc and it never cuts out because, I have been told, it uses radar. I have found several posts on the internet with other drivers having similar such problems - here is one. www.mybmwi3.com/forum/viewtopic.php?F=15&T=3059 of course, I can avoid this problem by not using the acc, but it is one of the options I wanted and paid for on the I3. We have not been in an accident thankfully, but perhaps others have. Other than this very dangerous situation, the I3 is a superb car.

- Las Vegas, NV, USA

2015 BMW I3 with range extender (rex) just hit 1000 miles. Had for 6 weeks. I was traveling down a freeway at 75 mph using my electric car. As the battery was almost out of juice, I knew the fuel range extender would kick in. However, when the extender kicked in, my mph immediately started to drop. Within the 15 seconds, I was down to 35 mph from the 75 I was traveling. I had the accelerator floored, but could not get any power to keep up with the flow of traffic. With my hazard lights turned on. My car and I safely navigated to the side of the road. Thank goodness there was not a car following to close or a semi truck. I would be dead or in a serious accident if there was. My concern, consumers are not being warned of this issue... here are a few more facts that are relavatn 1. when I drove the car the first timer he range extender kicked in. I was not dropped down to 30-35 mph, I was able to keep up with freeway traffic just fine 2.on December 29, 2015 II was traveling on a freeway at 75 mph. There was a slight incline. My electric had been used and the rex kicked in. The car immediately started to drop in speed. I had the accelerator pushed to the floor in hopes of getting the car back up to a safe speed. However, that did not happen. I had to navigate my dying car to the side of the road in 75 mph traffic. 3.immediately took the I3 to the BMW service provider. Instructed by the service dept this is working as designed. Error message of 0056 did not have any description on it. Not sure how the technician knew there was not an issue 4.instructed by service dept to go back to my sales person to be re-trained on my car. Why isn't there an indicator light warning the driver you will be loosing significant power and speed. Pull over to a safe mph? concerned for other consumers....someone will not be as lucky as I was

- Laguna Hills, CA, USA