Transmission question (CVT)

[catman85]

The Fusion has a CVT transmission, so why is there a D, L and R on the gear selector. If its a CVT should it just have D and R? How can a CVT have 2 ranges?

[murphy]

L is for descending a hill.

If the HVB is not fully charged regen is used to charge the HVB which provides back pressure.. If the HVB is fully charged then the engine spins up and acts as an air compressor to hold the car back for the hill descent. No fuel is fed to the cylinders so the engine isn't running.

[catman85]

That helps me understand, so, moving the gear selector into L is not changing gears but telling the computer to remap the engine for a decent. Right?

[catman85]

L is something like putting the engine into a Jake Brake mode? True?

[aschulz261]

It's not 2 ranges, it's 2 different modes of operation. A stated above, it can be used while descending a hill to help hold speed down without having use the brakes. I've always just used the hill descent button for that. I have never seen the need for the L range.

 

I have heard a few people say that they use L range to help the ICE warm up quicker on the first start of the day. I don't know if that helps. It's ALWAYS warm here.

[mwr]

Jake Brake mode?

What's that?

[catman85]

A compression release engine brake, frequently called a Jake brake or Jacobs brake, is an engine braking mechanism installed on some diesel engines. When activated, it opens exhaustvalves in the cylinders after the compression cycle, releasing the compressed air trapped in the cylinders, and slowing the vehicle.

[ptjones]

It's not 2 ranges, it's 2 different modes of operation. A stated above, it can be used while descending a hill to help hold speed down without having use the brakes. I've always just used the hill descent button for that. I have never seen the need for the L range.

 

I have heard a few people say that they use L range to help the ICE warm up quicker on the first start of the day. I don't know if that helps. It's ALWAYS warm here.

It would heat up the ICE faster by turning higher RPM's, but I'm not sure that it is fuel efficient to do it. ;)

 

Paul

[Griswald]

I wonder if the labels D, R, and L have more to do with the manufacturers making the vehicle more "normal" than anything. If there were only STOP and GO labels, it might make some feel uncomfortable, just like the fact that Ford had to program a creep mode into the programming when you take your foot off the brake, so it feels the same as a "normal" car.

 

Wish I could disable the creep and just put the gear selector in GO!

[ElectricFan69]

That helps me understand, so, moving the gear selector into L is not changing gears but telling the computer to remap the engine for a decent. Right?

In most modern cars, moving the "gear knob" is simply operating a switch set that tells the ECU what you want to do. The days of moving positions of hydraulic valves to make stuff happen ended with the advent of computer-controlled transmissions (of all types). In Ford's implementation of the Aisin design, the "B" position tells the ECU to maximize the powertrain braking - by regen, or when the battery is fully charged, by ICE compression and MG counter-torque to keep the ICE spinning faster.

[jdbob]

From the service manual:

 

"When the transmission range is in the low position, the transmission increases regenerative braking when the accelerator pedal is released to provide an engine braking feeling and increased battery charging."

[Simon Da Osam Paul]

so what is the difference between the L and the "Downhill" button which is on the side of the gear knob??

[talmy]

so what is the difference between the L and the "Downhill" button which is on the side of the gear knob??

 

I believe the "best answer" in this thread is actually a wrong answer. What was said "the engine spins up and acts as an air compressor to hold the car back for the hill descent. No fuel is fed to the cylinders so the engine isn't running." is done with the switch, not the L position, and happens regardless of the battery charge. That's been my experience. The L, as far as I'm concerned, is useless, and is there to make people used to conventional automatics comfortable. Until our Fusion, I spent 45 years driving a manual, so don't care. The quote above from the service manual describes it fine: "When the transmission range is in the low position, the transmission increases regenerative braking when the accelerator pedal is released to provide an engine braking feeling and increased battery charging." You can press the brake pedal lightly to get the same effect.

Edited August 19, 2016 by talmy

[Flávio Fraga]

The L uses de ICE to diminish the speed in hill descendings. Even with no use of gas the ICE acts as a braking device and increases the electrical regeneration.

Don´t be afraid to use it. it is stronger than the knob button in gear lever.