Tom M

I've had my 2011 CS for about a week and have been trying the auto stop/start the last few days during my commute. In the morning it seems to work as advertised once the car warms up. However 2 days in a row while on the evening commute it's behaved differently. It's stopped correctly at one spot but then not stopped later on at multiple locations when it seems like it should have (i.e. slowing for a stoplight and then fully stopping for an extended period) and the yellow indicator with the line through it appears.

The manual says this may happen with a low battery but I checked it last night and today and the voltages seems good. While running it shows 14.2-14.8 from idle to drive and when off it reads 12.19v at the posts and after sitting overnight it was 12.09v at the posts using a DMM. Right after a restart it does dip to 11.8v or so according to the dash reading.

This is all on flat roads so no strangeness there with being on a hill or anything. The only other possibly contributing factor is the outside air temp is in the 20-30 range but it's the same thing on the morning commute. The heater is on but it's certainly not on high at 74.0.

I'm taking it into the selling dealer next week to get the PCM updated to current version and get some other minor stuff fixed that was supposed to be taken care of prior to delivery but I'd like to have more info on this prior to simply saying that is doesn't seem to be acting right since it's a 2+ hour drive.

ndx

Tom M ... normal ... I wouldn't be to concerned ... I don't even use mine.

Sometimes it kicks in and sometimes it does not..

Tom M

I'm thinking if the battery is needing replacement I might get some relief since the dealership marked it as good as part of the CPO inspection.

John Welch.

I think a fully charged battery should be around 12.7 volts. 12.19 is nearly half discharged.

Tom M

I bought a CTEK 3300 and it will be here Saturday so I'll see what a decent charge does to the level.

RESP

I've used the auto stop/start feature in the city for some time on our 2012 Cayenne.

I've noticed when I am gearing down as I come to a stop it often won't engage the stop function and you get the yellow symbol with the line through it.

Also when I am driving in a more spirited manner (quick launches followed by gearing down to a quick stop) the auto stop won't engage.

When I am loafing along and driving very conservatively, the auto stop system engages most times.

Maybe the "spirited" driving non shut off is trying to keep the fluids flowing after you've thrown the vehicle around a bit?

Tom M

I actually think it was related to the level of the battery as it's been behaving more like I would expect since I've charged up the battery. Although the additional information is certainly welcome.

In reality it's not a lot of use for my particular commute as I've only got a couple of lights where I normally get hung up. Other than that it's backups at roundabouts and I can usually gauge that to the point that I don't ever really stop. If it was a more in-town type of commute with lots of stop lights I could see it being more beneficial.