As aberrent stated - that is the dynamic charge or energy regeneration system. You'll see it's action in the display under the tach. It is automatically turned on and off by the car's computer. I do not know the parameters used by the computer to decide when to engage and disengage, but it appears (based on my 3000 mi driving experience) to be when coasting or braking.
Originally Posted by The X Men
I agree, the ABS should not lock the brakes, in fact, it is a anti lock system to prevent locking. Sounds more like a braking problem to me, the brake froze somehow and then let go altogether causing the lurch forward.
When it is engaged, there is a noticeable drag. When it releases the sensation is the car lurching forward since drag is reduced. I have only noticed the drag/release when I am coasting or have the brake only very lightly engaged.
From your description, it sounds like it is working as designed.
But maybe I don't understand - when you say "everything locked up" and "brake froze" did the wheels lock and result in screeching tires and marks on the pavement?
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