power steering lexus LFA 2012 Technical Information / LEXUS 2012 LFA: INSIDE THE LFA

36
Shifting
With regards to the drivetrain, the steering wheel-mounted paddle shift switches
command the automated dry single-plate clutch and rear-mounted ASG (Automated
Sequential Gearbox) transaxle. This fully automated configuration allows the driver to
upshift (+) or downshift (-) while keeping both hands on the steering wheel.
When the driver initiates a gear change using the paddle shift switches, the ASG
computer automatically controls and coordinates clutch engagement, engine speed,
torque transfer and gear select and shift operations.
The engine-mounted dr y single-plate clutch and rear-mounted transaxle are
connected via torque tube to provide the direct feel of a manual gearbox.
The ECU manages gear changes to provide intuitive response to the driver ’s
a c c e l e r a t i o n d e m a n d s . D o i n g s o a l l o w s g e a r c h a n g e s t o b e c a r r i e d o u t
instantaneously, providing a nearly uninterrupted flow of power. The engine speed
is computer controlled on upshifts and downshifts in order to ensure smooth clutch
engagement.
Naturally, shifting can be accomplished manually via the paddle shift switches.
However, shifting can also be performed automatically in AUTO mode. Switching to a
different driving mode using the driving mode selector switch or operating the paddle
shift switches will resume manual operation.
When in a manually shifted driving mode, the shift speeds may be tailored to the
driver’s preferences. Using the shift speed selector, the shift speed can be adjusted in
7 stages to a minimum shift time of approximately 0.15 seconds.

44
Steering
The driver’s steering inputs are conveyed by a large-diameter main shaft housed
within an aluminum alloy steering column, then through a joint made as straight as
possible onto the intermediate shaft. From here, inputs are mechanically transferred
to the wheels by an aluminum alloy monoblock steering gearbox. This efficient flow of
steering commands helps ensure a direct steering feel and precise wheel placement.
Joint Column assist type EPS
Aluminum alloy steering column
Intermediate shaft
Joint
Steering gearbox
The LFA’s power steering system features a column-assist type EPS (Electric Power
Steering) system. This computer-controlled system takes into account factors such
as vehicle speed, steering effort and steering rate in order to provide linear steering
feedback. Furthermore, the teeth of the reduction gear, a section of the motor
responsible for sending large amounts of torque to the main shaft, have been coated
with power grease to reduce torque fluctuations and provide smoother steering feel.

112
Brake and Tires
Brake Calipers FrontOpposed 6-piston monoblock
Rear Opposed 4-piston monoblock
Brake Rotors CCM
(Carbon Ceramic Material)
Brake Rotor (diameter) Front
f390 mm x 34V
Rear f360 mm x 28V
Brake System ECB
(Electronically Controlled Brake)
Brake Fluid Type FMVSS No.116 DOT3
Brake Fluid Capacity RHD1.2L (1.3 qt., 1.1 lmp. qt)
LHD 1.1L (1.2 qt., 1.0 Imp. qt.)
Parking Brake EPB (Electric Parking Brake)
Wheel Size Front20 x 9.5J +45
Rear 20 x 11.5J +45
Tire Size Front265/35ZR20 (95Y)
Rear 305/30ZR20 (99Y)
Suspension Type FrontDouble Wishbone
Rear Multi-link
Steering Gear Type Rack and Pinion
Steering Gear Ratio 14.3
Lock to Lock 2.35
Power Steering Type EPS (Electric Power Steering)
Stability control VDIM (Vehicle Dynamics
Integrated Management)
Electrical System
Battery Size S75D31R
Voltage & Amp.hr. (5HR) 12V-56AH
Alternator Output 2,640 W
Starter Output 1.7 kW

116
Engine response 56
Engine speed control 40
Engine speed limiters 16, 17
Engine starting restrictions in
extremely low temperatures 17
“ENGINE START” switch 9
Engine switch 9
Engine type 16
EPB (Electric Parking Brake) 52
EPS (Electric Power Steering)
system 44
Exterior care 78
Exterior maintenance 78
FFlat bed transporting 100
Flat-bottomed steering wheel 45
Floating disc 53
Floating rotor 53
Floor mat usage 22
Floor-mounted brake pedal 51
Front brake caliper 52
Front brake rotor 53
Front counter gear 38
Front disc 53
Front rotor 53
Front suspension 47
Fuel 63
Fuel filler door 12
Fuel filler door manual unlock 95
Fuel gauge 63
Fuel level units selection 67
Fuel tank 63
Fuel tank cap 12
Fuel tank volume 12
Fuel type 12
Fuelling up 12
Fuse 93
GGas 63
Gas filler door 12
Gas filler door manual unlock 95
Gas level units selection 67
Gas tank 63
Gas tank cap 12
Gas tank volume 12
Gas type 12
Gauge 57
Gauge cluster 57
Gauges 57
Gear selection 36
Genuine leather maintenance 84
HHandbrake 9
Heel stopper 22, 51
Hood 12
Hood stand 12
IIdeal driving position 17
If the vehicle battery is discharged 94
Ignition switch 9

120
Speed Indicator 67
Speedometer 57, 67
SPORT mode 58
SPORT mode
(control characteristics) 26
SPORT mode (selection) 27
Starting off 11
Starting the engine 9, 1 0
Starting the engine by connecting
an external battery 98
Status 67
Steering 44
Steering adjustment 23
Steering column adjustment 9
Steering column shaft-mounted
EPS (Electric Power Steering)
system 44
Steering rack and gearbox 46
Steering system 44
Steering wheel adjustment 23
Steering wheel adjustment lever 9
Steering wheel adjustment
range 23, 45
Steering wheel position
adjustment 23
Steering wheel shape 45
Steering wheel telescoping range 23
Steering wheel tilt range 23
Stop and go traffic 37
Stopwatch 67 , 72
Suppressing dark current
(parasitic current) 93
Suspension adjustment 47
Suspension geometry 47
Synchronizer rings 39
Synchronizers 39
Synchros 39
TTachometer 59
Telescopic adjustment range 23
Telltale needle 71
Temperature display units
selection 67
TFT LCD panel 56
Throttle body valve opening
angle 33
Throttle response 33, 56
Throttle response adjustment 33
Throttle valve opening angle 33
Tilt and telescopic steering control
lever 9
Tilt range 23
Tilt sensor deactivation 102
Tires (vehicle long-term storage) 92
Tool bag 100
Topping up the oil level 69
Torque tube 38
TORSEN® LSD 39
Tow hook 100
Tow truck selection 100
Towing eyelet 100