It Looks Like You Need Help

by Tom Scocca

I was on my way up and out of town, following Google's orders to get to the Palisades Parkway in a rented Toyota Prius, when I hit a little bit of traffic—hardly any traffic, the bare minimum reminder that there's never a good way out of Manhattan—and I moved my foot from the gas to the brake, automatically, as one does. An instant before I pressed the brake pedal, the car started slowing down. 

It was a mild effect but also utterly shocking. What happens when I step on a brake pedal is wired into my muscle memory quite literally from head to toe. And this was something else. As I was trying to judge the car's speed and how much brake to apply, the car's speed was changing out from under me, on its own. 

In an unfamiliar car, in motion, I couldn't begin to figure out how to identify and turn off whatever feature was at work. Further along, heading into a long sweeping curve, I found myself fighting the steering wheel as the Prius disagreed with me about where to sit in the lane. It fought with me again when construction barrels squeezed in from the shoulder and I edged away.  

After I'd returned the car, I Googled “Prius brake assist default” to try to figure out what had been happening to me. At first, Google Search told me about the Toyota Pre-Collision System, which would have sounded an alarm, or would only have boosted the brake power after I stepped on the pedal. But I knew the Prius had braked silently, all on its own; also what Google had dug up a link to was an online manual for the 2021 Toyota Mirai, not the 2024 Prius.