I stopped at a light yesterday and the day before and the ICE will turn off, then turn on for a second or two, then off, then on for a second or two, etc. it did this for probably 15 seconds until I let my foot off the brake and coasted forward a few feet then stopped again. What the heck is going on. It's done it twice now. 2009, 97k miles.
What was your battery SOC (charge) level? If it was all 8 bars (full green), it may be trying to bleed off some excess charge from the battery. When it does this it behaves somewhat how you describe.
I have EngineLink for my iPhone and a wifi obd2 reader and I think it was in the high 70's. Is this normal behavior?!
Normal SOC is around 60 and the max is 80, so high 70s is indeed quite high. That 80% figure is under nominal conditions, too. If the battery was extra cold or hot at the time, you may have been under the "forced discharge" condition. The real number you need to look at is CCL, which takes all factors into account. So my guess is yes, your Prius was just doing what it is supposed to do to protect the battery.
