Sure Way To Prevent Dead Battery

[SnowStorm]

OK, the title is a "joke" but the rest of this post is not.  Here's what happened.

 

I'm sitting in the house one evening and started hearing an occasional faint sound I hadn't heard before.  It would last maybe 30 seconds then repeat a half hour or so later.  After about the third time, I start walking around and note it gets louder near the garage.  I open the door and there's The Enterprise purring along like a nice little kitty!  Good grief!  I know it never totally "goes to sleep", but starting up the engine?  What new failure mode is this?  I go get a key (thinking I'll have to cycle power), hit the garage door button and head for the car while trying to remember the symptoms of CO poisoning.  Getting in, I find the other key already in the ignition and the green "ready to drive" light on!  So that was it.  Car left "ON" after parking in spite of the warning chime.  It may have sat for an hour or more before starting the first time.  It would run a bit to charge the HVB and shut off.  I bet it could do this for months, left unattended!  I doubt there was much CO with all the air leakage around our garage doors (and short run time) but I'm still thinking of putting a CO monitor out there.

 

But that 12 volt battery would sure stay charged!

[plus 3 golfer]

LOL, I had a similar experience recently.

 

One evening I went in the garage to start the C-Max to test Forscan from my desktop computer and placed the Key FOB in the center cup holder. After maybe a 1/2 hour or so of playing around (getting in / out of the car several times during the testing) , I went inside for the night thinking I had shut the car off.  The next morning as I was getting ready to leave for golf, I couldn't find my keys  and after some thought realized that I must have left the keys in the C-Max.  I went into the garage and was struck by how warm it was.  I opened the door of the C-Max and it was even warmer inside the car.  That's when I realized the C-Max must have been running and sure enough it was in ready to drive mode.   When I got out, I felt the hood of the C-Max and it was very warm.   FE for that tank slipped a little. :)  I figured at least 3/4 gallon of fuel was burned over about a 12 hour period.

 

I'm surprised that I or my wife didn't hear it running but there's the garage door and a laundry room door in between plus the bedroom door when sleeping.  I did recall that our dog barked at least once which is an indication she heard something.

 

My 12 V battery was fully charged though. ;)

[scottwood2]

LOL.  Easy to do when the car is so quiet in running mode. 

 

I see trains running all the time in railyards.  Maybe C-Max's can start a new trend?   :happy feet:

[fotomoto]

Prius "campers" have reported an approx. 3/4 gal/hr burn rate doing this (with lite a/c use) while sleeping in their cars.  So assuming a full tank and a similar "idle" rate, the CMax should go nearly a day doing this.  

 

On a more serious note, I've also read reports of hybrid owners having the cars left on for several days by valets at airport parking lots.  That will run the car empty of fuel and discharge the 12v shortly after that.     :banghead:    Now that more and more vehicles are coming with push button start, that situation will, hopefully, diminish.

[hybridbear]

A friend of ours has had a 2nd gen Prius since the first year they came out. She has told us about doing this many times. It's understandable.