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Discussion Starter #1
If I am driving the car and have to stop at traffic lights I use the brake pedal to stop the car from moving and it seems that there is no electric drive when the pedal is depressed, when you take your foot of the pedal it is obvious that power is then applied to the traction motor and we get the familiar "auto creep".

If however you are stationary at traffic lights or a level crossing that are on a slight incline and you know you will be there for some extended period, I leave the car powered up and apply the parking brake, I notice that when I take my foot of the brake pedal the car sits down at the rear indicating that power has been applied to the traction motor. In the event that I leave the car in “D” or “L” will the fact that power is applied to the motor cause damage as the motor is not turning?
 

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:shock: The same happens with the Nissan Leaf.

It shouldn't do any damage. Well, at least I have been assured that it doesn't as far as the Leaf is concerned and I cannot think of why it might. A motor is just using EMF to rotate and so there is no gears or things to damage. A force of applied but resisted by the wheels just like it does when driving only the resistance is greater. It isn't like an auto box that has moving parts and hydrolic pumps that can wear or overheat if it isn't moving.

One word of caution though if you do put the electric parkbrake on and leave it in L or D...

The approved method of doing a hill start is exactly that... apply the park brake, put into L or D and press the accelerator. The park brake automatically releases and off you go without rolling backwards. If you ever put the park brake on but leave it in L or D at lights etc then just be careful not to accidentally touch the accelerator pedal or the brake will release and the car will roll forward.

I did that by accident myself. I was at the front of the queue for the lights and did as you describe... park brake on as it was going to be a few minutes but left it in D. I then reached to the back seat to get something out of my bag and my foot just gently touched the accelerator pedal. when I turned back to face the front I was moving forward. :shock:

It was the most gentle of touches yet the car released the park brake.

I now never leave the car in D or L if I have engaged the electric park brake. It scared me a little that is for sure. If I wasn't at the front of the queue I might have hit the car in front or worse... entered the junction on red!

At lights I either just leave it in D with my foot on the brake pedal. Or I will apply the park brake and nudge it into N. It is easy and quick enough to nudge it back to D when I am ready to go.

I never put the car drive selector into P unless I am actually parking. Then, if on a slope, I will put the selector to N first, apply the park brake and then take my foot off the brake pedal to allow the car to settle onto the brakes. I then move the lever to P. That way it stops the load being taken up by the gearbox lock pin... I know we don't have a gearbox in the traditional sense but we still have the pin!
 

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Just reading the manual and came across this, what defines a hill I am not sure

Note
Spinning the tyres or holding the vehicle in one place on a hill using only the accelerator pedal may damage the electric drive unit. If you are stuck, do not spin the tyres. When stopping on a hill, use the brakes to hold the vehicle in place.

Gary
 

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Discussion Starter #4
Ah yes, but the question is if stuck on a hill with the parking brake applied do you need to move the selector to neutral? If left in D, L or R will damage be caused?
 

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I have not read anything definative that requires you to shift out of drive, and the comments in the manual seem to suggest to me that as long as you have applied the brakes you are not stressing the system.
Wonder if one of the Ampera experts can enlighten us ?

Gary
 

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Discussion Starter #7
Yes I agree with what is said there but they are talking about the foot brake not the parking brake.

Stop the car, put on the parking brake and then release the foot brake and the back of the car will sit down if it is in D or L.

Tray it...
 

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Hi Ray,
Yes, got the same effect, also tried on level ground shifting between R and D, the outcome was the nose or tail dropped accordingly, obviously as you say with power being applied.

I suppose in my posts above I was pre-empting your question about leaving in D or L, with one of the answers in the Volt forum saying that there was "no value to putting your Volt into Neutral", which I take as being no problem with leaving in D.

Gary
 

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I think from this I deduce that in L or D power isn't being used if the foot brake pedal is depressed but it is when just the park brake is applid... would you say that is correct?

I suspect that the amount of power loss though is insignificant to our range.

For me the issue is about potential damage and I think the jury is still out on that one for me.
 

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Discussion Starter #10
Just spoken to Trevor (MyAmpera) and the Vauxhall line is that when the car is powered on and is stationary with the parking brake applied and no foot on the foot brake the "gear" selector should be placed in "N" or "P"

I have suggested that when the car is stationary and the parking brake only is applied no power should be applied to the motor as is the case when the foot brake is applied. Power should be applied when the accelerator pedal is depressed. This goes hand in hand along with the suggestion that the parking brake is applied automatically when the car is powered off.
 

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Fair enough. Nudging to N isn't going to be a problem for me whenever I apply the park brake... I do that anyway now to prevent the car launching should I accidentally dab the acellerator pedal (when the park brake automatically releases).

Thanks Ray :)
 

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Not sure about the parking brake, but when you apply the regular brake at a stop (with your left foot) and hold it while pushing the accelerator pedal (even all the way) The car's computer knows to apply only a very small amount of power to the electric motor, until you release the brake.

The tiny amount of power required to induce the creep function (like automatic transmission cars have) is nowhere near enough to hurt the car. And apparently, the Volt/Ampera's engineers foresaw and programmed for every contingency like this. The car's computer is smarter than humans..... :)
 
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