2008 Lexus GS450h traction control

18
GS_HV_U
December 12, 2007 3:33 pm
CAUTION
■General precautions while driving
Driving under the influence: Never drive your vehicle when under the influence of
alcohol or drugs that have impaired your ability to operate your vehicle. Alcohol
and certain drugs delay reaction time, im pair judgment and reduce coordination,
which could lead to an accident that will hurt or kill you, your occupants or others.
Defensive driving: Always drive defensively. Anticipate mistakes that other drivers
or pedestrians might make and be ready to avoid accidents.
Driver distraction: Always give your full at tention to driving. Anything that distracts
the driver, such as adjusting controls, ta lking on a cellular phone or reading can
result in a collision with resulting death or serious injury to you, your occupants or
others.
■General precautions regarding children’s safety
Never leave children unattended in the vehi cle, and never allow children to have or
use the key.
Children may be able to start the vehicle or shift the vehicle into neutral. There is
also a danger that children may injure themselves by playing with the cigarette
lighter, the windows, the moon roof, or other features of the vehicle. In addition, heat
build-up or extremely cold temperatures insi de the vehicle can be fatal to children.
■Dispose of the hybrid battery (traction battery)
If your vehicle is disposed of without the hybrid battery having been removed, there
is a danger of serious electric shock if high voltage parts, cables and their connec-
tors are touched. In the event of that your vehicle must be disposed of, the hybrid
battery must be disposed of your Lexus dealer or a qualified service shop. If the
hybrid battery is not disposed of properly, they may cause electric shock that can
result in death or serious injury.

26
1-1. Hybrid system
GS_HV_U
July 3, 2008 12:32 pm
High voltage componentsTake care when handling the hybrid sy stem, as it contains a high voltage
system (about 650V at maximum) as well as parts that become
extremely hot when the hybrid system is operating. Obey the caution
labels attached to the vehicle. Power control unit
Air conditioning compressor
Hybrid battery (Traction bat-
tery)
DC/DC converter
Service plug
Electric motor (Traction motor)
High voltage cables (orange
color)
Caution label

130
2-1. Driving procedures
GS_HV_U
May 13, 2008 3:11 pm
■When starting on an incline
The hill-start assist control may operate. (P. 200)
■For efficient use
●Put the shift lever into “D” when driving 
In the “N” position, the gasoline engine operates but electricity cannot be gen-
erated. The hybrid battery (traction batte ry) will be discharged requiring unnec-
essary engine power to recharge.
●Drive your vehicle smoothly 
Avoid abrupt acceleration and deceleration. Gradual acceleration and decel-
eration will make more effective use of the traction motor without having to use
gasoline engine power.
●Avoid repeated acceleration 
Repeated acceleration consumes hybrid battery (traction battery) power,
resulting in poor acceleration. Battery power can be restored by driving with
the accelerator pedal slightly released.
●Put the shift lever into “P” when parking 
In the “N” position, the hybrid battery (traction battery) does not recharge.
Leaving the shift lever in the “N” position for an extended period of the time may
discharge the hybrid battery. The vehicle cannot run if the hybrid battery is dis-
charged.

132
2-1. Driving procedures
GS_HV_U
May 13, 2008 3:11 pm
CAUTION
■When driving the vehicle
●Do not shift the shift lever to “N” while the vehicle is moving.
Doing so may cause the engine brake not to operate properly and lead to an
accident.
●Do not turn the hybrid system off while driving. 
The power steering and brake actuator will not operate properly if the hybrid sys-
tem is off.
●Use engine braking (downshift) to maintain a safe speed when driving down a
steep hill. 
Using the brakes continuously may cause the brakes to overheat and lose effec-
tiveness. ( P. 144)
●When stopped on an inclined surface, use the brake pedal and parking brake to
prevent the vehicle from rolling backwa rd or forward and causing an accident.
●Be careful when driving on slippery surfaces, as the vehicle may spin or skid when
downshifting, rapidly accelerating, braking or turning.
●Do not adjust the position of the steering wheel, the seat, or the inside or outside
rear view mirrors while driving. 
Doing so may result in a loss of vehicle control that can cause accidents that may
result in death or serious injury.
●Always check that all passengers’ arms, heads or other parts of their bodies are
not outside the vehicle, as this may result in death or serious injury.
●Do not drive in excess of the speed limit. Even if the legal speed limit permits it, do
not drive over 85 mph (140 km/h) unless your vehicle has high-speed capability
tires. Driving over 85 mph (140 km/h) may result in tire failure, loss of control and
possible injury. Be sure to consult a tire dealer to determine whether the tires on
your vehicle are high-speed capability tires or not before driving at such speeds.
●The driver should pay attention to pedest rians when the vehicle is powered only
by the electric motor (traction motor). Because there is no engine sounds, the
pedestrians may misjudge the vehicle’s movement.

145
2-1. Driving procedures
2
When driving
GS_HV_U
May 13, 2008 3:11 pm
■Downshifting restrictions warning buzzer (in the “S” mode)
To help ensure safety and driving perfor mance, downshifting operation may some-
times be restricted. In some circumstances, downshifting may not be possible even
when the shift lever is operated. (The warning buzzer will sound twice.)
■When driving with the cruise control syst em (or dynamic radar cruise control sys-
tem)
The engine brake will not operate in the “S” mode, even when downshifting to “5” or
“4”. ( P. 1 6 9 )
■Snow mode automatic deactivation
Snow mode is automatically deactivated if the “POWER” switch is turned to
ACCESSORY or ON mode after driving in snow mode.
■If the shift lever cannot be shifted from “P”
 P. 5 2 9
■If the indicator does not come on even after shifting the shift lever to “S”
This may indicate a malfunction in the transmission. Have the vehicle inspected by
your Lexus dealer immediately. 
(In this situation, the vehicle will operate as if the shift lever is in “D”.)
■When in heavy traffic
To avoid running the hybrid battery (traction battery) down, leave the shift lever in
“D” or “S”.

200
2-4. Using other driving systems
GS_HV_U
January 4, 2008 10:02 am
Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface.
■ Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding wh en swerving suddenly or turning on
slippery road surfaces.
■ TRAC (Traction Control)
Maintains drive power and prevents the rear wheels from spinning when
starting the vehicle or accelerating on slippery roads.
■Hill-start assist control
Helps prevent the vehicle from rolling backwards when starting on an
incline or slippery slope. It operates for approximately 5 seconds at maxi-
mum.
■ EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.
■Active stabilizer suspension system (if equipped)
Turns at smaller angles to main tain the stable vehicle posture.

461
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U
December 27, 2007 1:38 pm
FuseAmpereCircuit
8IG210
Multiport fuel injection system/
sequential multiport fuel injection
system, noise filter
9EFI No.210Fuel system, exhaust system
10H-LP R LWR15Headlight low beam (right)
11H-LP L LWR15Headlight low beam (left)
12D/C CUT30DOME, MPX-B
13IGCT No.37. 5Hybrid battery (traction battery)
14IGCT No.27. 5Hybrid system
15MPX-B7. 5
Power windows, door control system,
power seat, electronically controlled
brake system, combination switch,
electric tilt and telescopic steering,
gauges and meters
16DOME7. 5Interior lights, foot lights, vanity light,
gauges and meters
17ABS MAIN110Electronically controlled brake sys-
tem
18ABS MOTOR30ABS
19ABS MAIN210Electronically controlled brake sys-
tem
20F/ P M P25Fuel system
21EFI25
EFI2, multiport fuel injection system/
sequential multiport fuel injection
system
22INJ20
Multiport fuel injection system/
sequential multiport fuel injection
system

561
6-1. Specifications
6
Vehicle specifications
GS_HV_U
December 12, 2007 3:50 pm
■DOT quality grades
All passenger vehicle tires must co nform to Federal Safety Require-
ments in addition to these grades. Quality grades can be found where
applicable on the tire sidewall between tread shoulder and maximum
section width.
For example: Treadwear 200 Traction AA Temperature A
■ Treadwear
The treadwear grade is a comparative rating based on the wear rate of
the tire when tested under controll ed conditions on a specified gov-
ernment test course.
For example, a tire graded 150 would wear one and a half (1 - 1 /2) times as
well on the government course as a tire graded 100. 
The relative performance of tires de pends upon the actual conditions of
their use, however, and may depart significantly from the norm due to varia-
tions in driving habits, service practices and differences in road characteris-
tics and climate.
■ Traction AA, A, B, C
The traction grades, from highest to lowest, are AA, A, B and C, and
they represent the tire’s ability to stop on wet pavement as measured
under controlled condit ions on specified government test surfaces of
asphalt and concrete.
A tire marked C may have poor traction performance.
Warning: The traction grade assigned to this tire is based on braking
(straight ahead) traction tests and does not include cornering (turning) trac-
tion.