Brakes failed upon starting the car. multiple warning lights on the dashboard (brake, abs, traction control, and brake system) resulting in total brake failure - cannot stop the car with normal braking even while just putting the car into drive/reverse from park. started happening ~3 weeks ago. the only thing that stops the car is the emergency / parking brake. if pressing the brake pedal all the way, just before hitting the floor there is a loud popping / grinding noise and the parking brake (?) engages. the first time, turning the car off/on fixed it. we took it to our local nissan dealer, they said "could not find the issue in their system" and said it was a "fluke" and wouldn't happen again. happened again a few days later and turning the car off/on didn't help, and the car was stuck in our driveway. tried replacing the 12v battery, which fixed the issue temporarily. happened again a few days after that and had to get it towed back to nissan. *now* they found the issue in their system and think it's the "driven intelligent brake unit" and costs $2600+ to fix. they also say the "main engine harness" may need to be replaced for some reason as well, costing another $2400+. have contacted nissan usa, they told me they don't have a record of this being a problem with leafs (even though there are dozens of complaints on here) and refuses to provide assistance. this brake system is *extremely unsafe* for the driver & passengers, and everyone around it. my kids could have been near the car when it started moving on its own even though i was pushing the brake pedal. no one needs to die or get gravely injured because of this faulty system.
When the 12-volt battery failed on my 2015 nissan leaf, the car would still turn on and would move forward without pushing on the accelerator. the brakes did not work either. this happened to me both in a grocery store parking lot at night and then the next morning on a residential street. similarly, when it turned the car on in my driveway, i put it in reverse, and the car moved without me pushing on the accelerator and the brakes did not engage when i pushed on them. the car behaved this way 4 times, including once for the nissan dealership service worker who had to pull the car forward in the line of cars waiting to be serviced. after nissan replaced the 12-volt battery, the problem disappeared. several leaf owners have told me to report the problem, because it is a safety concern that the car can move but the brakes do not work when the 12-volt is failing. i called nissan to notify them of this problem but did not get a response beyond a call from consumer repairs saying she would make a note of it.
I've only had the car for 2 months, and the brakes have failed repeatedly, once about every 5 days on average. every time they have failed, it was when i start up the car, and put it in either forward or reverse. i usually pull forward into a parking spot, so i go in reverse much more frequently after starting up, but it has happened when going forward too. this is the failure mode. i start the car, while holding down the brake pedal, and then i put it in reverse. at that point the car starts rolling backwards, even though i'm still holding down the brake pedal. the brake pedal gets soft and when i floor the brake pedal, the car finally slows down and stops. another way to stop it is to put it back in park, but that causes it to jerk to a halt. needless to say, this is a scary scenario, and this frequently happens at my kids' school, where there are many kids and parents walking through the parking lot. in addition, the car also has some other problems. it sometimes starts a long uninterrupted beep when i turn off the car to get out. the beep goes on for minutes, and sometimes i see a warning light on the dashboard. finally, the card completely stopped working today. an error message of "t/m system malfunction" appeared on the dashboard, and i was not even able to put the car into neutral for the tow truck. the driver window did not work anymore. after attaching a battery charger to the 12v battery, i was able to put it into neutral, but not able to put it in reverse or drive, or even back in park. the car had more than half of its battery cells full, so the problem was not because it ran out of charge.
Tl* the contact owns a 2015 nissan leaf. while driving 20 mph, the vehicle suddenly stalled and failed to restart without warning. the vehicle was towed to the dealer. the technician was unable to diagnose the failure. the vehicle was not repaired. the manufacturer was notified of the failure. the failure mileage was 5,050. the vin was not available.