Took my Prius in for the ABS re-flash this morning, and they had the vehicle for less than an hour. When I got into it for the drive home, I noted that the traction battery was greatly depleted, down to two bars from nearly full, AND the indicated avg MPG had dropped from about 47 to 42. I asked the service writer for an explanation of the traction battery depletion, but he didn't know (one week on the job) so he went back to the shop. They told him that it was because the vehicle had been sitting ON in the shop during the service & wash, but I question how the traction battery could be drained that far that fast. I've sat in the vehicle on Ready for 10+ minutes motionless, and haven't seen the traction battery decline at such a rate. Anyone have a better explanation for the battery drop? Also, though I suspect this is true, are the battery drop & the indicated avg MPG drop connected?
That's really not that unusual when you look at the circumstances. The car was probably started, driven very short distances (Stage I where the propulsion is primarily from the traction battery), shut off, left in "On" condition. If the climate control was on during this that contributes too. I suspect that if you did a "pretend" session of driving the car out in your own neighborhood and drive way with similar times for shut down, leave the car sitting for a while not driving it, with your usual climate settings that you'd find it would do the same. so, bottom line...not a problem, they didn't do anything wrong, and there is absolutely no harm to your car...it'll take care of itself and 2 bars really isn't bad, your battery still had a SOC of around 50-60%.
If they had left the car running where it cycled the engine on and off (especially if you had left the heat and heated seats on) I can see the battery showing decreased bars and the MPG dropping as well...
I did this today because I was inflating my tires with an air pump plugged into the lighter. I heard the ICE cycling on and off. At the end, my trip MPG was down noticeably. Didn't notice a change in the battery level, but I'm not sure I checked its level at the start.
When I do my XGAUGE development I often sit with the car "ON" but in park .... and it will deplete the HV battery down to two bars before starting the ICE again, then it goes to 3 and the cycle repeats. Totally normal..... The car draws about 0.7amps to 1.7amps when turned on and not being driven.
