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I can never get the drive battery up to fully charged. It hovers between 1/3 and 3/4. Has anyone got an answer to this please?
 

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Normal. They are safe guarded from full charge/overcharging. You can get them full charge is you enter a mile or more long decline, 11-12%, with about 1/4th charge, and roll down using B mode, or whatever is that new models have for it. That's how I full charged mine.
 

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Normal. They are safe guarded from full charge/overcharging. You can get them full charge is you enter a mile or more long decline, 11-12%, with about 1/4th charge, and roll down using B mode, or whatever is that new models have for it. That's how I full charged mine.
Thanks for that. I'm not familiar with B Mode so will go a-hunting. Cheers.
 

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It used to be marked down by gear shifter. They call it something else now. Basically, uses engine as ballast to slow down vehicle and regens battery faster. Very kewl to use, actually.
 

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It used to be marked down by gear shifter. They call it something else now. Basically, uses engine as ballast to slow down vehicle and regens battery faster. Very kewl to use, actually.
Aha, thanks. My car is in permanent regen when braking or over-running. The electric motors convert to generators and charge the battery while the generator resistance slows the car. Cheers
 

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With influx of new model owners, there appears to be a lot of confusion and misunderstanding about B mode.
Not really asked about this, but I think it may be a good idea to put some clarity into this.

Before we go any further, one concept needs to be realized.

TOYOTA HYBRID VEHICLES DO NOT HAVE TRANSMISSION THE WAY WE ARE USED TO IT.

Hybrid Synergy Drive, or HSD, has PSD - Power Split Device.

Graham's Toyota Prius

(all references for Prius are basically same for Camry)

With this being said, what happens when you shift lever into any position? You are, simply, telling computer to change the PSD mode of operation. This is why Prii do not even have shifting lever, but a dingy little joystick in dash board, one of the main reasons I shall never buy one. It is nothing more than an electronic lever telling ECM (engine control module) what do you want to do, then it tells servos to adjust PSD accordingly.

As a result, this allowed Toyota to come up with B mode. B stands for "braking".

In a very simplified manner, and for those who are familiar with manual transmissions, B mode , for any practical purpose, is equivalent to braking with engine, in a car with manual transmission.

You chose B mode, ECU tells TCM - transmission control module - to couple one of the motor generators, or MG, with ICE - internal combustion engine. Engine is placed into "fuel starving mode", when no fuel is supplied. As a result, wheels are slowed down by resistance, produced by air being compressed inside the cylinders. Amount of this resistance is controlled by VVT-I, variable valve timing - intelligent system, bleeding air out of the engine, as needed.

Main difference between Hybrid ICE engine braking, and conventional ICE one is that fuel is not supplied and amount of resistance is electronically controlled.

Second very important difference is that, because TCH - Toyota Camry Hybrid - does not have conventional transmission - B mode can be used for normal acceleration. As soon as gas pedal is touched, braking with engine is stopped, and acceleration is resumed. The very moment gas pedal is released - power train goes into engine braking mode again.

Camry manual states that "to start moving, place gear selector lever in D or B position". Permanent use of B mode is not recommended, as "certain gears may be damaged" (Prius manual)

What practical purposes does B mode serve?

1. Very nice, smooth, slowing down the vehicle. I certainly use it on wet downhills, where chances of skid are higher, if normal brakes are applied. Vehicle Stability Control System takes longer to respond, than B mode. This is what B mode is primarily recommended for in manual.
2. Though it is still argued in this forum, B mode recharges hybrid battery faster, than simple inertial recharge from rolling in D mode or from regenerative braking. This is accomplished by MG supplying 30-40 Amp current to the hybrid battery, which is higher recharge rate, than other recharge modes.
3. B mode, AFTER THE BATTERY IS FULLY CHARGED, serves as waste gate equivalent in a turbo charged engine - by coupling ICE to MG. ICE propulsion "dumps" excess energy. Otherwise, in D mode, to accomplish same, ECU will turn ICE on and keep it running.
4. This is for drivers that actually DRIVE their Camrys, not just let Camrys "drive drivers". I use B mode for sharper, sportier cornering. Instead of using brakes before corner entry, I kick lever into B mode. It gives just enough braking to enter the corner faster than in D mode and, as I can accelerate right away, allows to pass corner apex faster, and exit corner at higher speed, by simply stepping onto the gas pedal. Then, after exiting corner, I kick lever back into D mode.
5. It is said, that B mode, due to this neat slow-accelerate-slow-accelerate feature, is used by drivers that cross-tour Prii and Camrys.
6. It is said - and I'll check it out winter time - that B mode permits much better stability on snow and ice.
7. Personally, I do use it for short, "burst" type brakings during normal commute, town or freeway. Whatever allows me to touch brake pedal less - is good.

Needs to be noted, that ICE resistance depends on vehicle speed. Max resistance is at speeds higher than RPM - revolutions per minute - limit for MG, which is, I believe, around 3500 or so RPMs. In older models, this was 42mph, in new ones - 45mph.

Is it safe to use B mode? Yes.
Does it save more gasoline? I do believe so, as it puts ICE in fuel starved mode. Also, it improves mpg by allowing to stay away from regular brakes. Also, recharging hybrid battery faster, it allows longer EV - electric vehicle - mode use.

Fun factor is also there, as it gives another option of controlling your vehicle. As in - driving it, not just sitting there.
 

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I know. I believe, it does have equivalent though, just name differently. I can't possibly see Toyota discontinuing a very helpful feature. It is, likely, called something else. I had this discussed before and, of course, forgot what that setting is called now.
 

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My drive battery on my 2019 Camry Hybrid LE become full. Its not always full just sometimes. When i say full i mean bars not max cell voltage.
 
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