Hopefully someone can add some color to this issue Just bought a 2017 Prius Prime Premium 2 days ago. Mother was driving on an open highway in the daytime at 75 mph. No cars in the vicinity Cruise Control button not set For some reason, the car started to decelerate gradually to around 40 mph ... Mother tried to accelerate because speed limit is 65 but it would NOT accelerate. She said she tapped the brake a couple of times and tried to accelerate but it wouldn't. She got scared, pulled over, turned off the car, and turned the car back on. It's "normal" now. Her buyer experience is now shot and she said she's scared to drive it. Has anyone heard of this issue before or could speculate based on what I wrote of why this may be? thank you
Wow, that can be a scary situation. Were there any kind of warning lights that came on during the drive? Get it to the dealership to be checked out. You pay this much money for a new car it should work perfectly.
Emotional prejudices like that are often difficult to "fix"; sometimes impossible. Consider calling the dealer and seeing if he has another identical one in a different color. Or take it in for a checkup and report back that they found something and fixed it.......even if they didn't. Given the history of Pruis dealer's diagnostic efforts, if there are no lights lit on the panel and no trouble codes set, it is likely that all you will get from the dealer is a shrug of the shoulders; as in, we have no idea.
If it was my gen 3 (I only say this because I'm not sure what the gear selector looks like on the prime) I would suspect the P (park) button got hit accidentally, which will throw the car in N instead at high speed for obvious reasons. But then I think if you tried to accelerate a warning message would pop up saying you were in neutral.
If the dealer won't or can't fix it I would report it to the NHTA. These are the kind of things where people get hurt or killed. I would tell the Toyota dealer my plan, they don't like bad dealership or corporate press.
I agree the most probable explanation is park or neutral by accident. If no one was around to witness it, she might have failed to notice a warning while she was trying to figure out what was going on.
@huskers's suggestion to have the car checked by a dealer is a good one. If P, N, or R was selected by mistake or through some malfunction while the vehicle was traveling at speed, this would be recorded in the Vehicle Control History, which can be retrieved by a dealer or anyone with a Toyota Techstream diagnostic system. See my previous posting for more about this.
All of you have valid points and much appreciated! I will definitely ask the dealer to look in the Vehicle Control History to see what was recorded. I asked if she accidentally hit somethin and she said no. My question is, if the gear selector was accidentally hit to B, shouldn't it "downshift" from 75 to 40 at a faster pace than 5 minutes though? In addition, wouldn't the car still allow a driver to accelerate? Also, is it possible to hit the "Park" button while driving? That sounds sort of weird that it would allow that. My thoughts exactly. I hope it's something along the lines of "user error" versus car malfunction like they had with the acceleration issues 10 yrs ago
B mode would still allow acceleration. Hitting P acts like a quick shift to neutral when you're going too fast to go straight to park
B mode will decelerate much faster than N, and will produce noticeable engine RPM noise while doing so. And you'd still be able to accelerate in B, so selecting N via the P button is most likely. To select N with the gear shift, you have to move it to the left and hold it a couple of seconds. Maybe she placed something, a purse or a phone, near the P button. You might want to go on a ride with her and note her habits. She might just need a bit more familiarity with the Prius. If it's her first one, the controls are quite different from conventional cars.
Obviously, I don't have a Prime! But that's interesting. So, what happens in EV mode when placed in B?
Where? Can you give Google Map or Google Earth points so we can understand where it happened? What time? Where does she stow her purse or purchases? An intermittent problem will come back. I agree that the symptoms are consistent with flipping into an unnoticed "N". Bob Wilson
Probably the engine stared at this point....once the speed hits 75 it kicks out of EV Mode into HV, when mine does this it definitely feels like it suddenly decelerates. If you’re not expecting this, you could panic and think something was wrong. Nothing against your mother at all....I’ve had moments when my paranoia got the best of me and I thought the car was broken....when it was just me!
Not true. I have often driven at more than 75 in EV mode and it doesn't "kick out". I believe the prime will go up to 84 mph on just the battery. When the ICE comes on, you can feel a slight change, but it doesn't suddenly decelerate. Maybe a change of one or two mph, but with a slight pressure on the accelerator, it will continue at the desired speed.
I should have been more clear......when the engine kicks in (for whatever reason that it does) there is a drop in power. I personally feel like I have to press a LOT harder on the accelerator to keep up the speed I’m going (and if you don’t, the car will decelerate). Especially if it’s a high speed like 75 mph. Someone driving an unfamiliar car, not expecting that, might panic and think something was wrong with the car. Your mind/memory of the situation kind of overreacts when you panic, especially when you are driving and something scary happens that makes you feel out of control. That’s all I was trying to say, my apologies.
