Sometimes the level of the hybrid battery is less than 33% and the bars are colored purple.

What is the cause of that? Am I doing something wrong here? Am I leaving the car on, unintentionally?

TCH 50th Anniversary Edition

Ours has never done that, not even once that we've observed in almost a year. I don't know how often this behavior should be seen and the car still be considered to be operating "normally".

First of all the battery is kept at between 65% to 80% of full charge to prolong it's life, so when the indicator shows battery fully charged , it is not but somewhere around 80% of full charge, same when low charge is being shown.
Second of all my car will run on battery, if lets say I get stuck in heavy traffic, which is everyday and it will run off the battery until the indicator goes purple. When it does and it shows about 2 marks, then the ICE will kick in and recharge battery to at least 1/3 full (as indicated on display) even if I'm not moving at all.
It is normal part of the operation of the car, so don't worry about it. The computer is monitoring state of charge of the battery and it will act accordingly by letting it charge or discharge. Green means full charge (actually 80% of full charge), blue means middle range and purple means battery is empty (in reality discharged to 65%) and this is full operating range of the battery. If you leave the car parked and use lights and AC to discharge battery quickly, it will be cycling between blue and purple all the time , starting the engine to recharge ever so often. The only time you won't see purple is if you never let the car run on battery alone for too long ( for example highway driving, short stops followed by hard acceleration etc.)

Thanks for the information. I was concerned that I left the car on inadvertently or something.

TCH 50th Anniversary Edition

The only time I would be concerned is if you know for the fact that you left the car fully charged at night and come back next time to battery that is discharged (purple). I think reading lights can stay on at all time without ignition on and they kind of hard to see in a daylight, but they would discharge 12 V battery, not the powertrain battery, unless you left the ignition on, but then the ICE would kick in and keep traction battery charged. I'm not sure what would happen if you left the ignition in ACC state , but keep in mind , if the car is not properly shut down it will give you warning beeps when you take your key out and I think it will also not let you lock it.

One way this could happen would be if the car was left in neutral gear but not turned off, as when the off button was pressed twice by mistake. Normally if it is still left on, but in park (not ideal, as someone could get in and drive off without the key), the battery will slowly run down but as needed the ICE gas engine will cycle on long enough to recharge and then turn off, repeating as needed to keep the battery charge from getting too low (until the gas tank finally empties).

But when the car is left in neutral gear and not turned off, the ICE engine is unable to recharge the motor and both the accessory and main battery charge could be completely lost, requiring the car to be towed to the dealer to reset and recharge the main battery. Although the 12v accessory battery can be recharged at home, the main battery cannot. I recall one person posting a dead main battery that required a tow to the dealer and he later recognized the car had been left in neutral (and likely still on) in his garage overnight.

When leaving the car if you hear 3 beeps the car is NOT off, or if a long beep is heard either a door is ajar or it is not left in park. When locking the car (with either the button on the car door or the remote), anything other than a single beep indicates a problem, and should be rechecked.

only time I've seen purple is in heavy traffic moving no more than 5MPH, so it did what it was supposed to do.

If you mean it's purple when you fire it up in the morning when it was green when you shut it off I'd be talking to the dealer like mentioned above

I just found out that my daughter turned on the reading lights in the back seat.

I just thought it was peculiar that the battery was discharged to the purple range.

TCH 50th Anniversary Edition

I believe the reading light in the back comes off the other (12v) battery. I've been wrong before, though, so take my electrical engineering with a grain of salt.

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