sakumar

The excessive whine that I notice is when I step lightly on the brakes. I do hear the softer whine of the motor when accelerating, but that is not as loud as the regenerative braking noise. Neither is this louder whine present when I am coasting (i.e. foot off the accelerator, but not on the brake). In this case too, the motor is acting as a generator but it is not as noisy. I am speculating here, but during regenerative braking, the system must be engaging some additinal gearing which has the affect of (a) more rotations to the electric generator/motor as compared to coasting and (/B) slowing down the vehicle. Perhaps it is the additional gearing, or maybe it is the higher rpm of the generator that is responsible for the whine during braking?

On Page 10, and again on Page 411, the manual states: When applying brakes, you may hear a sound coming from the regenerative brakes. However, this does not indicate any trouble. The sound is noticable, but I assumed it is normal. Now I think I am going to seek out another 400h owner (I have seen another one in the parking lot at work) or have it checked out by the dealer.

It's not from inside the cabin. It is a whine from the Electric motor/generator when it is engaged during regenerative braking. It is more pronounced when on a down-slope and I am coming to a dead stop (say) at a stop sign. It is not a screech that is typically heard when the brake pads are worn out. Perhaps the Original Poster had a different observation but the description was similar to what I had noticed in my one month old RX400h. Also, if the radio/cd is on then the whine is not that noticable.

I got mine last month and it does the same thing. The whine sounds (to me) like a police siren in the distance. The manual states numerous times that the brakes make an unusual sound so I guess that is the way it is supposed to be. I must say that after driving around a bit, and with the music on, it is not as disconcerting as it first was. I don't think it is less loud, just that I am getting used to it.

Rx330Driver -- thanks -- I tried the procedure a few more times but it hasn't worked. The manual is a little sketchy on details. For instance it says move ignition to ON, but does that mean engine should be in "Ready" state, also you can't move the shift lever to "N" without pressing the brake but it doesn't tell you that. I suppose I can ask them to set it when I get them to set the other Personalized settings as you suggest. Chubyball -- I belive you are referring to a different personalized setting -- where a single key click will open all the doors instead of requiring one click for driver door and another one for all the remaining doors. At least in my reading of the manual this one is not user settable.

I know about Lexus Personalized settings, but having recently bought an RX 400h I noticed on Page 44 of the manual that the Automatic Door Locking/Unlocking functions are user settable. But after trying the procedure (ignition ON, move gear lever to "N", within 10 seconds hold down door lock for 5 seconds) I wasn't able to change it to "lock on vehicle speed". Anyone else tried this and is there a special trick to getting it to work? Moreover, on rereading the Personalized Settings, it only offers "lock when shifting out of park" or not. Not "lock on vehicle speed", which is what I wanted and is offered as user settable on page 44. thanks.