I been meaning to post about the "Creep Mode" for a while now and warn you creeper to stop it. If you hold the brake and don't allow any creeping, you save energy. The program works with the ABS system and when you let it creep, you begin sending current to the drive motor. If you hold the brake pedal for no vehicle movement, no current is used or activated to the drive motor or Traction motor as it's called.

The reason you roll back when you release the brake pedal while stopped on an incline for a bit is because it takes a second for the creep mode to sense the reverse movement and adds more power to the traction motor.

If you folks need more info, I'll see if I could find the "Creep Mode" patent again.

GaryG

 

Thanks for the clarification. Being used to manual transmissions, I always thought the creep in automatic transmissions to be a bad idea (unless there was some reason that I am unaware of). A car should not move unless told to by the driver unless it is neutral IMHO. I was not happy to see Ford actually put effort into emulating this "feature" but it is nice to know that at least it is not wasting energy.

Cheers,
rcomeau

 

The creep also is a safety feature. It it were not there, soon, especially if this were your only car, you would get used to the zero creep, and fall into a habit of NOT applying the brake at stoplights, etc. This would lead to many accidents as the car would roll down a slight hill not perceived by the driver, or even the wind could push you while you were looking down and you'd not notice till you hit something.
I remember Ford engineers saying that they wanted to both simulate a traditional automatic, as well as force people to apply the brake at stops.

I notice on some radio stations I get an electrical "whine" over the speakers... only when I'm standing still, only in EV, and only with my foot on the brake. Anyone else notice this? Even at 1mph the noise immediatly goes away. ???
-John

 

I've never heard that myself... is it only on AM?

 

Yea, I've noticed that also but never really paid much attention to it.

~John

 

Current is still flowing. The creep with the BOO switch on is designed to simulate the torque converter creep on a conventional automatic trans.

 

It wouldn't make sense to waste battery energy by torquing MG2 when the car is stationary with its brakes applied sufficiently firmly that it won't move. Certainly, in the TCH, there's no energy flow to MG2 in this condition. The interesting question is how the designers know when they don't need to send power to MG2. The answer, in the Toyota hybrids, is to use an additional "stroke simulator" hydraulic cylinder. It provides the normal brake pedal "resistance" that lets the driver feel how much force he/she is applying. The car then decides, based on this force amount, how best to apportion the total force between the regenerative braking (via MG2) and the friction braking. Regenerative braking stops when the car is almost stationary, and then only friction braking is used to stop and hold the car. If the driver then eases up on the brake pedal somewhat, this is sensed and power is sent to MG2 (and so indicated on the power-flow display) to cause the car to start to creep. I'd guess that the FEH probably does something similar.

Stan

 

Coming from a stick background, I call it a danger feature. I don't quite get how guaranteeing the car will move forward on a flat surface and hit something prevent the car from hitting something. How have the millions of manual transnmission cars managed all these years?

I always thought the creep was a side-effect of the automatic transmission that was not intended by the inventors, but tolerated and now has become expected. Kind of like how some blind groups are asking that hybrids and electrics be fitted with noise makers so they can hear us coming.

Anyways, my 2¢ worth.

Cheers,

rcomeau

 

Stan, it's enlightening to have you post in our FEH/MMH section. I just passed on more information I learned from my long research of my FEH to help the group share the improved mileage I get on a daily basis. Some wish to dispute my research and findings with BS and no reference.

The people lurking this site need to join and ask me questions about my MTE and how to save gas. Choose and pick my methods, but you can save at the pump.

GaryG

 

I'm sure you're right about this. I think what John was saying was that people who are accustomed to driving automatics need for these vehicles to behave like automatics or there could be trouble.