The Toyota Prius’ shifting is regarded as a classic feature.
It protrudes from the dashboard like the classic Alfa Romeo’s shifter. From it’s anything but conventional.
The gearshift is one of the driver’s main interfaces with the Prius’ intricate electrical, mechanical, and software engineering.
The Prius shifter does have one feature that has always been a mystery.
You have the typical “reverse,” “neutral,” and “drive” options, as shown in the picture below. There is no “park,” but there is a button on the dash for it. (This shifter, by the way, is from a 2016 Prius that we examined, albeit the part has been on the car for a while.)
Many people appear to believe that “B” enhances regeneration and sends more energy back into the system since the Prius has “regenerative braking,” which returns otherwise squandered energy from braking to the hybrid drivetrain.
But that is wholly incorrect. Since I’m supposed to know something about vehicles, I know because I was mistaken about it.
The “B” produces “engine braking,” which simulates the actions of a conventional transmission by simulating a downshift to slow the Prius down when it is descending a slope.
Why? if you’re traveling up a protracted, steep hill, to avoid overloading the brakes. The feature should be used at that time, much like a lower gear in a stick shift or a lower setting on an antiquated automatic transmission.
Tell the driver of a Prius to keep it in “D” the next time you see them driving around in “B” while you are in the vehicle.
In This Article...
What does Toyota’s B gear do?
The most straightforward definition of Gear B is “braking.” Similar to changing a manual gearbox to a lower ratio on a lengthy downhill journey, the B gear in the Toyota Prius or any other hybrid vehicle serves as a lower gear with a special purpose. The vehicle’s speed is hindered when it descends a slope in B gear because of higher engine drag.
B gear is a drag-inducing part of hybrid cars’ regenerative brake systems.
Driving in B gear causes the friction and drag to create electricity, which fuels the battery of the vehicle. The main objective when descending a long, steep hill is to progressively downshift to reduce engine braking.
B gear can also be used instead of the brakes, particularly while climbing a long, steep slope. This makes it a fun feature to experiment with while also extending the lifespan of your brake system’s components.
When should I shift into Prius B gear?
The gear shift on a typical car is analogous to the electronic mode selector used by the Prius. The Prius includes a power button, a park button, and a selector for modes R N D and B instead of a traditional car’s modes P R N D 2 1 (park, reverse, neutral, drive, second gear, first gear) (reverse, neutral, drive, and engine-Braking).
The driver NEVER needs to switch to “B” mode during routine driving (Engine braking mode). The following methods are optional. When driving down a long, steep incline (such as a mountain road), “B” mode is recommended because using the brake pedal to adjust speed could cause the brake pads to overheat and fail.
In a typical vehicle, the driver responds to that circumstance by reducing speed to an appropriate level and engaging a lower gear (2nd or 1st). As a result, the engine must spin more quickly than it should, “losing” energy through vacuum losses but also assisting in maintaining a safe driving pace without scorching the brake pads.
The driver of a Prius responds to the circumstance by switching to “B” mode. This instructs the Prius to try to mimic “engine braking” in a traditional car. The Prius will accomplish this utilizing either regenerative braking or high-RPM zero-fuel-flow engine braking, depending on the vehicle’s speed and battery SOC (state of charge).
Engine braking is ineffective because it turns kinetic energy into heat by using the engine as an air pump. Regenerative braking that isn’t essential wastes energy during the conversion process. (Regenerative braking is beneficial when used in place of friction braking, but it is less effective than coasting at a constant speed.) Because of this, “B” mode is not suggested for everyday driving and will not recharge your batteries more effectively than just braking. You can “downshift” into “B” mode on a Prius, just as you might do when traveling down a long, steep hill in order to protect your brakes. The technology won’t allow you to shift in a damaging way because “Shifting” is entirely electrical. (You won’t get further than neutral if you attempt to shift into reverse while driving swiftly forward.)
The “B” mode can be utilized to increase the range of the EV battery in the case of the Prius “Plug-in” model, which has an EV drive mode. If in hybrid mode, you must first convert to EV mode before engaging “B.” This works well while approaching intersections since it eliminates the need to use the brakes before reaching the intersection. Each time this procedure is applied, the EV mode’s range is typically increased by.1 to.2 miles.
How does the Prius perform when it snows?
I was able to drive the Prius on several icy and snow-covered roads before the December temperatures threatened to reach a record high for Chicago on the last day of my loan to see how it handled the hazardous winter weather.
The Prius is a front-wheel-drive car with all-season tires as standard, according to Toyota. All-season tires are adequate, but winter tires give better traction and performance.
I observed no difference in tire traction throughout my test compared to any other all-season-shod vehicle I had been evaluating.
The Toyota Prius also tends to understeer, which means the front end stays moving straight even as you tilt the steering wheel to steer into a bend, making it a generally predictable vehicle to drive in the snow. Every time I tested this, as soon as I let off on the gas or used the brakes lightly, the front end of the Prius found traction, allowing me to make the turn. Once more, this experience is comparable to other front-wheel-drive cars I’ve driven in snow.
What has changed
The car’s brakes felt a little “grabby” in the snow, which took me off guard a few occasions. This is mostly because the regenerative braking mechanism of the gas-electric hybrid car uses energy lost during stopping to recharge the battery. Before you come to a complete stop while traveling at a slow pace, there is an abrupt increase in braking force, which causes the automobile to jolt to a stop. It took some getting used to, but when I wasn’t wearing my cozy but cumbersome winter boots, I was better able to modulate the pedal and had smoother stops.
How is the B gear used in an automatic vehicle?
At any moment while driving, choose B. When the accelerator is released while the hybrid battery is charged, the automobile brakes using the electric motor in the B position. This increases the number of times the hybrid battery can be recharged because charging also happens without the driver depressing the brake pedal.
It is possible to manually shift into lower gears from the B position. The gear being used (from 1 to 8) is displayed on the driver’s display.
- To change down even more, press the gear selector again in the reverse direction.
- To shift down to the next lower gear, press the gear selector once in the reverse direction.
The car must have steering wheel paddles in order to manually shift to a higher gear.
To get back to the D position, forward-press the gear selector.
To prevent jerking and stalling, the gearbox shifts down automatically if the speed drops to a level that is too low for the specified gear.
Normal mode
Normal mode is ideal for consistent, daily driving. In essence, it is a Toyota Prius’ factory setup. The heater and air conditioner will run as efficiently as possible in regular mode, and the gas pedal will be responsive (but not overly so!).
The usual mode is ideal for your daily journey around the city because it revolves around striking the ideal balance.
Can you always operate a vehicle in B mode?
There are oddities with B-mode; I’ll speak from experience with the ZE50; I’m not familiar with the i3, Tesla, or other models.
I’ve discovered that B-mode can be activated continuously. B-mode doesn’t forcefully slow down the automobile above 70 km/h (45 mph); instead, it acts more like D-mode. It starts to feel a little strong below 70 km/h. It is quite strong at speeds under 50 km/h (30 mph).
Both when the battery is cold and when it is fully charged (more than 93%), B-performance mode’s is constrained. The car continues to slow down at a rate that, in my opinion, is similar to what would occur if the battery were warm or not fully charged, but I suppose this is accomplished through friction braking.
You get used to it, but if you’re coming from a ZE20 or ZE40, the regen from those earlier models will be missed. At first, B-mode could appear tricky, but you might become used to it.
Note that unlike Tesla, where pressing the brake pedal activates the friction brakes, Zoe has decoupled brakes (managed by software), so whether you hit the brakes or utilize B-mode, you’re likely to get the same level of regen.
Can Prius be used in the winter?
The Toyota Prius has some respectable winter driving performance thanks to built-in technologies that improve stability and traction. Traction control, electronic brake force distribution, anti-lock brakes, vehicle stability control, and all of these contribute to safe winter driving.
How can I improve the performance of my Prius in the snow?
It’s crucial that all four wheels have snow or ice tires. The Prius may be able to drive more effectively with only two up front, but stopping and control are unlikely to significantly improve. Retain proper tire inflation at all times, regardless of the season, to maintain maximum efficiency.
Does a Prius’s gas mileage suffer in cold weather?
Fueleconomy.gov claims that temperatures below 20 degrees Fahrenheit can reduce a hybrid car’s fuel efficiency by between 30 to 34%. If your Toyota Prius typically gets around 50 mpg, you will now have to make do with a more typical 33 mpg average. That’s still not that horrible, to be honest, but it’s a sizable hit.
We recently drove a 2021 Toyota Venza for a week in a climate where the outside air temperature was consistently between 30 and 40 degrees Fahrenheit as an example from home. Although it isn’t quite the pre-described 20 cold weather zone, it had the desired effect on the car’s total fuel economy. In the end, we were able to achieve an average of 33 mpg as opposed to the combined driving estimate of 39 mpg from the EPA.
Should I take D or B to drive?
By simply releasing the accelerator, “B” provides far greater regen. With little experience, this enables you to drive with practically just one pedal. It works well for commuting in cities where you regularly have to slow down for traffic lights or just regular congestion. Additionally, it is advantageous when going downhill.
D is more effective in circumstances with generally constant speed, such as freeways, and is better at gliding.
I virtually solely drive in B. For owners of models from 2011 and 2012, this is almost equivalent to the Eco setting without sacrificing acceleration (more accurately acceleration for a given distance of the accelerator).