09 IS rolls back
#16
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I've noticed that the feature only works on inclines that are not too steep. I've also noticed that on steep inclines when my car starts to roll back, when I hit the gas pedal a bit, the traction control kicks in.
#18
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It's also in the manual...I live on a hill. When I back out of the drive way the rear of the car is on the downhill side. If I carry any backward moment the car will roll down the hill. Even if make sure the car is at a complete stop before taking my foot off the brake, the car will start to roll ever so slightly and you can kind of feel the car trying to keep it stopped.
#20
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Alot/quick jump of gas + incline = spinning tire(s). That's why your traction control is kicking in. Be a little easy on the gas going up a hill unless you want to send it sideways...which we all get the urge to do from time to time.
#21
Pole Position
Our cars (A/T only) are equipped with a feature Lexus calls "hill start assist".
However, if you ask me, it is a gimmick, as the car isn't actually "equipped" with any special electronic or mechanical device preventing roll back. The natural tendency for an A/T equipped car to creep forward in gear is enough to keep the car still on a slight incline. This is right out of the owners manual.
However, if you ask me, it is a gimmick, as the car isn't actually "equipped" with any special electronic or mechanical device preventing roll back. The natural tendency for an A/T equipped car to creep forward in gear is enough to keep the car still on a slight incline. This is right out of the owners manual.
#22
Lexus Fanatic
Our cars (A/T only) are equipped with a feature Lexus calls "hill start assist".
However, if you ask me, it is a gimmick, as the car isn't actually "equipped" with any special electronic or mechanical device preventing roll back. The natural tendency for an A/T equipped car to creep forward in gear is enough to keep the car still on a slight incline. This is right out of the owners manual.
However, if you ask me, it is a gimmick, as the car isn't actually "equipped" with any special electronic or mechanical device preventing roll back. The natural tendency for an A/T equipped car to creep forward in gear is enough to keep the car still on a slight incline. This is right out of the owners manual.
#23
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yup, i agree. i've tried giving it juuuust enough gas to get going uphill, and it still throws traction control. only difference is giving it a lot of gas makes the car go herky-jerky, while giving it a little starts it going smooth as butter. but both instances still throw the trac light.
#24
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Join Date: Nov 2007
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I tested the roll back effect on the steepest hills in San Francisco the other day. I literally took my foot off the brake pedal and I did not move back an inch or creep forward at all either. Neither did it roll back when I began to give it gas.
#25
Manual says:
But for me this feature works only on a slight hill, on steep hill it rolls back...
(2007, IS250, AT)
HAC*
(Hill-start Assist Control)
When the vehicle starts off on a steep or a slippery hill, HAC detects the backward
movement of the vehicle and effects 4-wheel hydraulic pressure control to reduce
the backward speed of the vehicle.
(Hill-start Assist Control)
When the vehicle starts off on a steep or a slippery hill, HAC detects the backward
movement of the vehicle and effects 4-wheel hydraulic pressure control to reduce
the backward speed of the vehicle.
(2007, IS250, AT)
#26
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Our cars do have it, i have a 08 IS250 and my driveway is on a hill i noticed when i let go of the brake the car rolls back a little and then the brake comes on, i can see the brake light on the window light up by its self
#28
Lexus Fanatic