Here's another question regarding the B setting:

We recently ditched our 1998 Land Cruiser for a 2010 Highlander Hybrid - We live in the mountains and I am regularly going up and down passes. In my land cruiser, I had the option of gearing down...now, I have this B mode on the transmission column. I've used it as I would in my old car, but I hate the sound it makes as it slows the engine down...Although the engine doesn't get hotter, it sure sounds like the engine is revving too high for comfort!! So, I recently discovered, as I descend in B, if I ride the accelerator pedal, it actual decreases the engine noise, yet still slows the car. And the gas engine never engages (Without my foot on the accelerator, the engine tends to slow too much...)

Has anyone else used the accelerator in conjunction with the B mode? I called the dealership and they had no answers for me...I've looked in the manual to no avail...I even sent an inquiry to Toyota.com and they simply said that the B does not over-rev the engine. However, they never addressed my use of the accelerator when in B mode...ANYONE? I would love to know if I'm doing it right as we are in the middle of winter and we've had some lovely icy / snowy roads lately...

Thanks in advance for your help...

 

I believe that when you are in B and put your foot on the accelerator, you are in normal driving mode. As soon as you take your foot off the pedal, you are back in engine braking. As such, you can (in certain situations where warranted) have in in B, accelerate as needed and then resume braking.
Even though it sounds awful (EDIT...I changed this part... -> and it sounds as if you're doing damage), the noise isn't indicative of any harm to the engine.
This is what I learned when I was asking these questions when I got my car.

 

I tried using the B mode a few times going down a rather steep grade down a mountain. It sounded like the engine was revving at a high rpm. I found I could actually drive around 40 to 45 mph while in the brake position.

I read somewhere that your not suppose to drive with the lever in B. I also found out the B mode uses the engine at times for braking, re-generative braking is also used and if need the physical brakes are then used. I sure wish they had put in a second gear (ratio) selection to use for mountains.

When in Drive you can use your brake pedal till your battery shows full charge, If you use the brake pedal for the re-genitive braking. Once the battery shows full charge the car switches to the physical brakes. They may get hot rather fast if you ride them for any length of time.

You would think using the brake pedal would also use the engine somewhat for slowing the car, but I don't' think it does.

It would be nice if Toyota would have installed a wire wound heat dissipation coil maybe under the car to put the extra amps into when braking down a mountain at 40/50 mph. Although, the two internal generators might overheat if used for any length of time.

I wish I had the Toyota shop manual to read the details of the workings of the B mode. That would be most interesting to see how it all works.

 

I'm not quite sure I understand...the noise is doing damage, but it isn't indicative of any harm to the engine? so is it or isn't it doing damage? I wish Toyota had something more robust to say about this B shift than the little two-liner explanation in the manual....Thanks for your help

 

So, should I just keep doing what I'm doing? or will the internal generator overheat? Yikes, I'm not liking the sound of all this...and I, too go down these passes between 40-50mph, but I hate riding the brake so the B has been a nice choice...it keeps it at a steady pace (as long as I have my foot on the accelerator -as I explained in the previous post...) Wouldn't it have been nice if Toyota had addressed these issues in their manual - or even with their dealerships...Different dealerships say different things, but nobody knows how to respond to the accelerator and B driving...

Thanks...

 

Wow, thanks for pointing out my typo!
I meant to say "it sounds as if you're doing damage"
I'll go back and edit the other post.
Thanks!

 

Lets get few things straight: TCH has CVT , there are no gears per se, so therefore there won't be L1, L2, just one B for engine breaking, controlled by computer according to car's speed. So if you're going down the hill at 20 MPH or 80, the computer will decide what "gear ratio" is needed when switched to B and put proper drag on the wheels. The same computer will try to protect engine from overspeeding, battery from overcharging and electric motors from overheating. Driving in B when not required is not recommended as much as it is not recommended to drive in L1 or L2, low gear in "normal" car, since the engine has to work harder, at higher speed. Drive normal car in L1/L2 on highway and you'll blow the engine as well, after few months, due to much higher stress and RPM, I would imagine TCH would be similar. On the other hand using B on the long, steep downhill could sometimes be helpful, since prolonged friction breaking could overheat the breaks and make them fail, even if it takes much longer than normal car, due to regenerative breaking using electric motors. In other words TCH already uses sort of engine breaking (electric motors) when just pressing breaks, so B mode is not as essential to protect breaks downhill, however B mode should be helpful on extremely long and steep hills, when regenerative breaking is not enough to slow the car down and using mechanical breaks is required for longer time. In normal use generators won't overheat that easily, otherwise we would already read about it here many times over, after all we all drive our cars normally and people who live in the mountains have no choice but drive there. I drove mine, used B mode when needed in the mountains where you could smell other cars burning breaks like crazy and I had no problem.




[quote=rburt07;218327]

I read somewhere that your not suppose to drive with the lever in B. I also found out the B mode uses the engine at times for braking, re-generative braking is also used and if need the physical brakes are then used. I sure wish they had put in a second gear (ratio) selection to use for mountains.



It would be nice if Toyota would have installed a wire wound heat dissipation coil maybe under the car to put the extra amps into when braking down a mountain at 40/50 mph. Although, the two internal generators might overheat if used for any length of time.

 

The B mode only enables engine braking. It is not like a low gear in a normal Auto trans. If you have the car in B, and accelerate then it is the same as in D. It only has an effect when you are applying less gas than is required to keep it at or to increase your current speed.

 

I sure wish Toyota would put a red led in the speedometer area. One that would light anytime the metallic brakes are being used. I would then feel a lot better about coming down some steep mountain, like a 17% grade in the B mode.

 

The sensors, etc. would probably add $100-200 to the car, not to mention an additional complex system that can fail, etc.
These cars are sophisticated enough.
I think they would be better off not wanting people to fixate too much on what is being used. The driver should use one pedal to go and the other to stop. That's hard enough for some drivers to master, but if they add in the "your using this braking system" it would only confuse them further.
Just my humble opinion.