Found On the Road Dead

[Russael]

This is simply incorrect. I am an electrical engineer by education and I taught power system while in graduate school. Electric motor does not spin freely when no electric power is connected. You need to have force to spin the motor and it becomes a generator.

 

OK.  I'm not trying to sound like a smartypants with this question, but how much force is needed to spin a motor with no electrical connection, and no place for that generated energy to go?  A 4,000lb car, on a slight incline, should be able to spin MG2 very easily.  I can also spin an alternator by hand, and with a quick twist of the wrist, it'll spin for a good 7 seconds if the bearings/bushings aren't shot and the car being off.

 

While I was fighting with the Focus Electric, I had put it in R and it rolled forward slightly (after I thought I got it started, but it was just in power-on mode), either due to the divots in the asphalt, or a slight incline it was on as well.

 

 

 

The generator, electric motor, and ICE are all interconnected through a planetary gear system.  The ICE has a clutch to disengage it, but the generator (and most likely the electric motor) do not.

 

I thought MG1 (the generator) acted as the ICE's clutch...?  Without a counterforce from that motor, the ICE simply spins it and won't move the car.

Edited March 23, 2014 at 01:22 PM by Russael

[larryh]

The generator is used to control the planetary gear system.  The chart above shows how the RPMs of the generator are no longer proportional to the car's speed when the ICE is on.  The generator has slowed down significantly and there is now significant torque supplied by the generator.  I believe a clutch is used to disengage the ICE when the ICE is off. 

[Russael]

The generator is used to control the planetary gear system.  The chart above shows how the RPMs of the generator are no longer proportional to the car's speed when the ICE is on.  The generator has slowed down significantly and there is now significant torque supplied by the generator.  I believe a clutch is used to disengage the ICE when the ICE is off. 

 

I don't think so.  If you look at that Prius link, you'll see that MG1 simply spins in the opposite direction when only MG2 is in use.  The ICE is connected directly to the planetary gearset with no indication of a clutch.  When the ICE is on and propelling the car with no energy being sent to MG1 (in free-spin), the car is basically being driven by the ICE and MG2's counter-force.  The belt driven CVT (think snowmobile) is basically 2 variable clutches.

 

There was a long video on youtube as well showing how the eCVT was assembled through the varying generations of the Prius as well.

 

Here it is for the 3rd generation, which I believe is the same thing in the Fusion (30 minutes long too): 

 

Edited March 23, 2014 at 01:23 PM by Russael

[larryh]

Here it is:

 

http://www.fordparts.com/Commerce/PartDetail.aspx?n=zFzo5S6J%2bhRe4We6D8O5Rg%3d%3d&id=270031670&m=2&search=true&year=2013&make=Ford&model=Fusion

 

The video above shows the clutch plate at the left.

[Russael]

Yeah, I stand corrected.  Even the Prius video shows the same kind of friction clutch.

[vett93]

I went to the parking garage and used the Bubble Level on my Samsung S4 smartphone to measure the slope of the parking space. I measured 5 times on a few locations on that space, and got numbers from 0.3 degrees forward to 0.2 degrees backward. So for practical purpose, the parking space is flat.

[Rexracer]

Thanks, Ashley. I'll PM you. But can you please answer the question below. Others on the forum tried to help me but I am not sure they have the correct technical info.

 

My question is: Does the car provide any engine/motor braking if the car is off and the transmission is in "R"?

 

If the answer is yes, then others' suggestions do not make any sense. This is because the car moved forward when I put the transmission in "R".

 

If the answer is no, then isn't it a design and safety issue?

 

I need to know the fact. It would be greatly appreciated if you can consult the technical folks at Ford and answer my question.

 

As JATR4 said, there is no engine braking in ANY automatic transmission car, when the engine is off. We do not normally experiance this in a normal car, since you would hear the engine is off, and not put it in drive/reverse, etc.

 

I have done the exact same thing as you several times, my driveway has a slight incline and I will either not have my foot on the brake, or not have the transmission in park hit the button move the selector and then roll forward (due to gravity). My experiance is once you have done this, it takes a bit of playing (put the car in park, cycle the on off with the foot on the brake, etc) to get the car to actually be "on" and "ready to drive". I dont think its an issue with the car at that point, I think its me not understanding the state the car is in, to then get it back into "on" "ready to drive" state.

 

Annoying yes, but once you understand what the car is "thinking" you will get it.

[Rexracer]

I went to the parking garage and used the Bubble Level on my Samsung S4 smartphone to measure the slope of the parking space. I measured 5 times on a few locations on that space, and got numbers from 0.3 degrees forward to 0.2 degrees backward. So for practical purpose, the parking space is flat.

 

Park the car in the same spot, push start/stop with your foot off the brake "on" not ready to drive, put your foot on the brake, shift into drive/reverse/neutral whatever, let up and see what happens (being ready to brake).

 

Heck make a video of the process so we can all see what happens. ;-)

[vett93]

First, I want to thank you all for trying to help me out. I have not ruled out that it was due to my own user error. It is a brand new car to me and I have to learn how to use it properly. I also want to point out that my previous car and my wife's Lexus have keyless entry/start systems as well. So I am used to pressing the brake pedal first before starting the car.

 

As I pointed out in my previous post, the parking lot is flat. I am trying to figure out why it went forward when I put the transmission in reverse. 

[vett93]

Hi vett93,

 

Once you send me over your info, I'll put you in touch with someone who will be able to address those questions for you. :)

 

Ashley

 

Hi Ashley,

 

Brandy from Ford regional center called me. All she told me was that if the dealer cannot reproduce the problem, there is not much she could do. I asked her to connect me to tech support staff at Ford. She said all she could do is connecting me with the dealer's service department.

 

She did do one thing for me though. She confirmed that the dealer was not telling me the correct information when I took the car there for inspection. According to her, it is not Ford's policy that dealer should not generate a ticket if they cannot re-produce the issue. Basically, the Ford dealer either lied to me or told me the false information.

 

I was treated very well by Mitsubishi dealer in both purchasing and service. Well, I did not have any defect with my Evo at all. I just took it to dealer for services. The dealer for my wife's car, Lexus, treated me very well also. Sad to report that I have a sour taste with Ford. The car is not even one week old. My first new car was a 1986 Mustang. Its reliability and dealer services were bad then. This is the reason I did not buy any more Ford cars until last Friday. Almost 30 years later, the experience is still bad.

[Energized]

 I got out the car and found my parking was not straight. So I went in the car, started it, put it in reverse, and pressed the accelerator pedal. Instead of going backward, the car moved forward slowly and hit a metal fence and incurred some minor scratches.

 

 

As others have said, the condition you describe is indicative of the vehicle being in Accessory Mode instead of Ready to Drive Mode.  

 

The fact that the vehicle "moved forward slowly" even though you were in Reverse and pressing on the accelerator pedal would, to me, confirm that the vehicle was in Accessory Mode.  

 

If the vehicle had moved suddenly or something more than 'slowly' would indicate something completely different.

 

 

p.s.   Speaking of Lexus/Toyota,  didn't they just pay the Justice Department $1.2 Billion for how they treated customers?  Talk about a sour taste.

Edited March 21, 2014 at 01:33 AM by Energized

[http]

If you had the car started and in Reverse,the backup camera should have activated.  Can you recall if that was the case?  This is my first car with a backup camera and I transitioned from a manual transmission.  That took a while to get used to (I still look for the clutch petal sometimes) and I relied on the backup camera as a second check that I have the car in the proper gear.  I usually back in to a spot in my parking garage and have sometimes gotten confused about backing out of a parking space that I've already backed into. The backup cam has caught me before I embarassed myself. I will never buy another car without a backup cam.

[FordService]

Hi Ashley,

 

Brandy from Ford regional center called me. All she told me was that if the dealer cannot reproduce the problem, there is not much she could do. I asked her to connect me to tech support staff at Ford. She said all she could do is connecting me with the dealer's service department. ...

 

vett93,

 

If you're still experiencing a concern, I recommend visiting a different dealer for a second opinion, and then checking back in with your CSM. She'll be in the best position to help you get this resolved.

 

Ashley

[Russael]

The following is a plot showing the RPMs (the RPMs shown in the chart have been divided by 100 to fit on the graph) and Torque for the generator.  Initially, the ICE is off (Absolute Load of the ICE is 0%) and the generator RPMs is proportional to the car's speed.  The torque is negligible--it is just spinning and not consuming or generating much power.  When the ICE turns on, the torque increases and is proportional to engine load.  The RPMs slow down.  The ICE is spinning at 1500 RPM. 

 

 

If you don't mind me debating this slightly more... I'm still thinking that the friction clutch is never totally disconnected from the powertrain.

 

I rewatched the Prius video and noted that they called that clutch a 'torque dampener'.  He didn't mention that it is disconnected.  It sounds more like they use it as a shock absorber of sorts.

 

Also, while he was showing how the car behaved in all electric mode, the ICE plate (the friction plate) never moved.  If it were disengaged, it should move or be able to move.  The Prius eCVT link I provided also shows that the planetary gears (that are connected to the friction clutch) do not move unless the ICE is on.

 

I simulated, via that link, the ICE being on at 1500 RPM and varied the speed of MG1, from 0 to 55MPH, and you can control how fast either motor spins (the ratio is locked) while maintaining that RPM from the ICE.  Once MG1 begins applying counterforce is when the car begins to move via ICE power, and MG1 begins to slow down.  That's how that torque band changes and how MG1's RPM changes while keeping the ICE the same.  However, it doesn't show where powerflow is going either.  If you were driving at say, 55MPH, all electrical energy should be focused on MG1 only, with the car being in charge maintain mode (neither adding nor taking energy away from the battery).  MG2, even though it is the main traction motor, is just along for the ride unless the car goes in to charge assist mode (where it's using all three to move the car, say while you're accelerating).

 

This is what makes the most sense to me.  Without an engineer to answer those questions or describe it in more detail (especially the need of the friction plate), I don't know or understand the need for it outside of my speculation of it being a shock absorber.  I did hit up Wiki and saw that some eCVTs don't have a clutch at all.

Edited March 23, 2014 at 01:44 PM by Russael

[larryh]

By disengage, I mean the car does whatever is necessary to remove the ICE from the planetary gear system.  The ICE RPMs are zero and the Torque applied to it are minimal when the ICE is off.   In addition, the Generator and the Motor now both spin at the same RPM, but in opposite directions, at a rate which is 10.4 times as fast as the front wheels spin.  I can observe the RPMs and Torque on all three:  the ICE, the Generator, and the Motor.

[viajero]

By disengage, I mean the car does whatever is necessary to remove the ICE from the planetary gear system.  The ICE RPMs are zero and the Torque applied to it are minimal when the ICE is off.   In addition, the Generator and the Motor now both spin at the same RPM, but in opposite directions

 

That's my understanding.  Spinning the generator (MG1) and motor (MG2) in opposite directions at the same speed is what effectively "disengages" the ICE.  The ICE can stay connected to the planet carrier and not turn or feel any (or at least not very much) torque.

 

The trick to the whole thing is the computer adjusting the MG1 to take up the slack in rpm between the wheels and the ICE.  That's how it emulates a CVT - you can run the ICE at any speed relative to the wheels.

 

By either applying an electrical load to or forcing electrical power into the MG1, the computer can also make up the difference in torque between the traction motor (MG2) and the ICE, as well as the rpm.  It can make the MG1 be a drag or a boost as necessary.

 

Seeing that Prius animation years ago helped to sell me on a Ford Energi.  I love that system; it's so simple and elegant mechanically.  Of course the complexity is in the software which has to decide when to feed how much electrical power into or out of MG1 and MG2 to keep the whole thing turning smoothly.

[larryh]

This is what I observed for my commute home today at 23 F.  The HVB battery temperature was 25 F.  For the EV portion of the drive, the motor consumed power from the HVB while the generator generated a small amount of power.  The ICE RPMs were 0 and the torque was minimal.   As usual, the motor and generator RPMs were equal, but in opposite directions.

 

While driving on the freeway with the ICE on in EV later mode, the roles of the generator and motor were reversed.   The motor generated about 6.5 kW of power, while the generator consumed 4.2 kW of power.  The net SOC change on the battery was a small loss of 0.1%.  I have no way of determining what happened to the net 2.3 kW of power between what the motor generated and the generator consumed.  Some of it when to power accessories, but they consumed probably no more than 0.3 kW.  Some of the loss is associated with charging and recharging the HVB.  Some of it is associated with converting electricity to mechanical power and vice versa which is not 100% efficient.  But I don't know what happened to the rest. 

Edited March 23, 2014 at 11:24 PM by larryh

[vett93]

As others have said, the condition you describe is indicative of the vehicle being in Accessory Mode instead of Ready to Drive Mode.  

 

The fact that the vehicle "moved forward slowly" even though you were in Reverse and pressing on the accelerator pedal would, to me, confirm that the vehicle was in Accessory Mode.  

 

.....

 

Are you able to move transmission shifter to "R" or "D" when the car is in Accessory Mode? With my car, I cannot move the shifter out of "Park" until it is in the Ready to Drive mode.

[JATR4]

Are you able to move transmission shifter to "R" or "D" when the car is in Accessory Mode? With my car, I cannot move the shifter out of "Park" until it is in the Ready to Drive mode.

You can too.  Push on the brake pedal and shift out of Park while in accessory mode.  It is really easy to do.

 

Step 1.  Get in the car and push the start button without  pushing on the brake pedal.

Step 2.  Step on the brake pedal and shift from P to R or D.  You are now in accessory mode.  The car will roll forward or backward if you are on an incline.

 

That is all that is required.  The car will not be ready to drive until you shift to P or N, push on the brake pedal and push the start button again.

 

You did steps 1 and 2 when your car rolled forward and was damaged.  The car was in accessory mode instead of ready to drive.  You pushed the start button BEFORE you pushed on the brake pedal.

Edited April 4, 2014 at 06:27 PM by JATR4

[larryh]

By disengage, I mean the car does whatever is necessary to remove the ICE from the planetary gear system.  The ICE RPMs are zero and the Torque applied to it are minimal when the ICE is off.   In addition, the Generator and the Motor now both spin at the same RPM, but in opposite directions, at a rate which is 10.4 times as fast as the front wheels spin.  I can observe the RPMs and Torque on all three:  the ICE, the Generator, and the Motor.

I believe the answer to what happens in EV mode is here:

 

http://www.google.com/patents/US20110263379

 

See paragraph 30.

 

When the powertrain battery 12 is acting as a sole power source with the engine off, the torque input 18 and the carrier assembly are braked by an overrunning coupling 53.

 

It states the planet carrier is braked.

[Energized]

Are you able to move transmission shifter to "R" or "D" when the car is in Accessory Mode? With my car, I cannot move the shifter out of "Park" until it is in the Ready to Drive mode.

Yes, the shifter will move out of Park when in Accessory Mode (starter button light is flashing).

 

The exception is if your charge cord is attached. While the charge cord is attached, you can not move the shifter out of Park.

[Cairo94507]

I would bet operator error as well.  Sorry for your experience; I hope your car was not damaged badly.

[meyersnole]

Yes, the shifter will move out of Park when in Accessory Mode (starter button light is flashing).

 

The exception is if your charge cord is attached. While the charge cord is attached, you can not move the shifter out of Park.

 

I have experienced this behavior before as well and wished it acted differently. You think you pushed the brake before the start button, but evidently not soon enough.

 

I understand why you need to be able to move it to N in ACC mode, but I have made this mistake before as well. One of the downsides to keyless start I guess (have not driven any other keyless systems so do not know if there is a better way.)

[vett93]

I just checked my wife's Lexus. One cannot shift the gear out of Park in ACC mode. On the user manual of her car, it has a section about forcing the shifter out of Park while in ACC mode. One has to use a flat head screwdriver to push a shift lock override button.

 

For the record, I have not run into the same issue again after owning the car for 2.5 months. So it is probably my operator error. 

[meyersnole]

It happens to me from time to time... usually when I am in a hurry  :)