Alright when driving in B is the engine running to help slow the car or is it the traction motor that is slowing the car?
Anyone?? I know it's 'probably in one of the several manuals that came with my new P but I much to lazy to open them. Hell, I only finally opened the hood to put more wiper fluid in!
Above 24 MPH, B always gets worse gas mileage than D.when slowing. You want to use B at the top of long downhills that will fill the battery past Toyota's ideal. (This is JUST like when you would use L in an automatic, but the Prius is not in a Lower gear, it uses engine Breaking)
exactly. no one really knows what's happening internally when it's used. toyota just says it's to reduce brake wear.
According to my HSI, it is using the electric motor to slow the car up to a certain speed and then the ICE kicks in and the brakes the car.
??? We do know what's happening, at least the general idea, if not every detail. In "B" the system uses a motor (MG1) to apply torque to resist being spun by the wheels. That forces the engine to spin faster than it otherwise would, absorbing some of the excess energy that would otherwise have to go into the battery or friction brakes on a serious downhill. If you must step on the brake moderately at the same time, the effect is increased, so the engine spins even faster. Don't use "B" except on long, steep mountain descents that would fill the battery or require heavy use of the friction brakes. It's just an alternate way of throwing away energy when that's necessary, much as one might downshift a conventional automatic or manual transmission for the same reason.