Will running the AC while parked discharge the battery?

If you have it in READY mode the engine will come on and recharge, yes.

But, if you just put it in Accessory mode, it will drain the HV without running the ICE at all. Have to watch that.

 

Also, if you do this with the transmission in neutral.

 

Actually, the A/C doesn't run in accessory mode, just the fan. So while you could theortecally discharge your battery with the fan, it'll take a heck of a lot longer.

 

What if it’s in park and you sit in it for a while it’s running? Does this drain the EV battery?

 

What is accessory mode?

 

if you are in park with the car in ready mode, it will use the 12 volt and hybrid batteries as necessary, and run the engine to recharge them. no worries.

acc mode is pushing the start button with foot off the brake. not advisable for more than a few minutes.
some think it's a good way to listen to the radio, etc. but the 12v can drain really quickly

 

To have the original post member understand it better when car is on ( light ready on) and in P or in D when the AC discharge the big battery the engine will come on like if you have regular car turned on with AC on and in park. You can leave the prius for days like that a long as you have gas. I think Toyota made this as the hybrid system would otherwise ruin the car right away

 

Zombie 16 year old thread.

The hybrid system is designed to discharge the battery and then re-charge it from the gas engine......for almost ALL of it's functions.
EXCEPT when the car is in Neutral.
Thus it is not a good idea to run the A/C while going through a "drive through" car wash.
All other "normal" situations, the car will take car of itself.

 

Good way to tell if the hybrid battery is worn out is to see if it tanks to one purple or no bars at all going through a fast food line with the ac on or just sitting at a light. If its doing that its Stage 1 of battery failure.

Hybrid battery failure in a 07 G2 is becoming the number one post on this site.