What could be the reason for the gear shift paddle in the Tucson falling into D gear on its own after being replaced?

What could be the reason for a Haima S5, 2016 model Enjoy Edition, not moving after shifting gears without accelerating?

When the old model Vito is at a red light and you shift from N to D, causing the car to lurch forward, what could be the reason?

What could be the reason for a vehicle with an 8-speed automatic transmission to jerk when shifting from 3rd to 2nd gear?

What could be the reason for not being able to shift gears when the car is cold?

Guys, I'm really freaking out. Just now, while driving smoothly, the D gear light (the one on the gear shift) started flashing, and the dashboard showed "Please shift to D gear first before selecting the appropriate gear." I was in a panic and didn't know whether to press the brake and shift to P gear or shift to P gear and then to D gear, and then it prompted "Speed too high to shift into D gear (or maybe P gear, I forgot)." It was terrifying, the car felt like it was in neutral and there was no power when I pressed the accelerator. I managed to park on the side using inertia, shifted back to P gear, and then to D gear, and it resumed normal driving. I want to ask you guys, what's going on here exactly? Is there a specific part that's malfunctioning?

Car enthusiasts: Sometimes when driving a small car, the D gear won't shift up. The RPM suddenly goes up, but the gear doesn't match. What could be the reason?

The battery status is normal. What could be the reason for not being able to start the engine after turning it off?

What could be the reasons for not being able to shift gears?

What could be the reasons for not being able to shift gears?

When shifting from D to neutral, there is a clicking sound. What could be the problem?