I-stop Started

[dad of jon]

Hi, I was debating if I should put this under the electrics or engine section, but figured it could go in either, so put it in the welcome area instead.....

anyways, I'm at traffic lights a couple of times in the morning work commute with the fan on 2 bars blowing to the windscreen (demist) the aircon is on eco mode. The auto lights are off. The engine is still idling. So the windscreen now has no mist on it all. I press the mode button to direct warm air to the front vents to warm up my hands a bit and the I-stop comes on. Since I've noticed this the I-stop has never activated with the fan directed onto windscreen.

I wouldn't have thought blowing air on the windscreen rather than through the front vents would use up so much more power that I-stop would not activate. Maybe the designers assumed that when on windscreen setting it's important to keep the air flowing for demisting purposes and that I-stop is not appropriate in those circumstances.

Either way, If you think your I-stop doesn't active as often as you think it should, try the mode button, to change from windscreen to face.

 

[brandini]

It's not power, defrost runs the AC

 

[Perusal]

Think this will depend upon how much 'reserve' power you have in hand by which I mean power necessary to restart the engine.You mention that this happens on your commute, how long a commute? If it's a relatively short commute maybe the system hasn't generated enough spare capacity to restart the engine given the a/c is also fired up to clear the window. However when the a/c is off the system recognises it does now have the necessary power in reserve and stops the engine.
I saw an incident recently where 2 minutes into a journey I pulled up at a set of traffic lights and the engine stopped automatically as one might expect. However I did have the a/c on and then without warning, and whilst still stationary, the engine restarted itself about 30 seconds later whilst I was still at a standstill and hadn't done anything at all.
In summary I think it's an "intelligent" system that balances a desire to stop the engine to save fuel against the required power to restart the engine.
Interestingly my wife questioned the wisdom of the system the other day until I was able to point out that in 4 months of ownership and 3500 miles (no commuting) the engine had been off for 1' 36". Now that must have saved some fuel.....

 

[xtrailman]

I've had the I stop restart itself after it shutting itself down, and I've been sat doing nothing, so to me it shouldn't have switched off in the first place, all its doing in wearing the starter motor out.

Another odd thing is the car when starting cold sometimes revs to near 2K, but NOT every time, even though the blue engine cold light is on.

 

[brandini]

If i-stop is never used the capacitor will wear out so some operation is probably for system checks and maintenance usage (like a generator).

 

[alex1706]

I've had the I stop restart itself after it shutting itself down, and I've been sat doing nothing, so to me it shouldn't have switched off in the first place, all its doing in wearing the starter motor out.

Another odd thing is the car when starting cold sometimes revs to near 2K, but NOT every time, even though the blue engine cold light is on.

I think it is probably very intuitive, re the restarting itself at lights, mine does that quite often. I put it down to either the pressure in the brake servo has dropped, or the internal comfort needs a boost, either air-con or heater. To be honest doesn't bother me.

Heres one, mine is an auto, and I can be stopped on a slight downhill slope and I-Stop has actuated, if I then take my foot off the brake whilst still in neutral it will start to roll then the engine will immediately start without me selecting drive. Very smart.

I am also impressed that the "hill assist" works on a down-slope as well an an up-slope.

The engine high rev on start-up I can live with, and in any case slip it into gear/drive & the revs drop back to about 750.

Alex

 

[Dr_Watson]

Are you sure it was in Eco mode? If you are in Eco mode with vents norton the windscreen and you switch to windscreen, it automatically disables Eco mode and switches to ac only. Then maybe when you switched back, Eco mode is enabled again (although I am not certain about this ) and the iStop activated...just an idea.

 

[dad of jon]

Are you sure it was in Eco mode? If you are in Eco mode with vents norton the windscreen and you switch to windscreen, it automatically disables Eco mode and switches to ac only. Then maybe when you switched back, Eco mode is enabled again (although I am not certain about this ) and the iStop activated...just an idea.

Yes, did the same yesterday, when you select windscreen it does go to full AC but I press the AC to go to eco, just to squeeze some more mpg out.

Then as soon as I pressed mode to direct air to face vents the I-stop came on. I have seen a someone post somewhere to say their I-stop doesn't come on. The fix could be as simple as switch to face vents and AC eco.