2010 Lexus GS450h stop start

219
2-4. Using other driving systems
2
When driving
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
■Reduced effectiveness of EPS
The effectiveness of EPS is reduced to prevent the system from overheating when
there is frequent steering input over an extended period of time. The steering wheel
may feel heavy as a result. Should this occur, refrain from excessive steering input or
stop the vehicle and turn the hybrid system off. The system should return to normal
about 10 minutes.
■VGRS is disabled in the following situations
●During stopping or the steering wheel has been moved for a long time while
driving at lower speeds.
●After the hybrid system is restarted at less than -22°F (-30°C).
CAUTION
Any of the following conditions may result in an accident which could cause death or
serious injury:
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded.
●The vehicle hydroplanes while driving at high speed on a wet or slick road.
■Stopping distance when the ABS is operating will exceed that of normal condi-
tions
The ABS is not designed to shorten the vehicle’s stopping distance. Always main-
tain a safe distance from the vehicle in front of you in the following situations.
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or roads with uneven roads
■TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRAC is operating. 
Do not drive the vehicle in conditions where stability and power may be lost.

459
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
CAUTION
■When raising your vehicle
Make sure to observe the following to reduce the possibility of death or serious
injury.
●When using a floor jack, follow the instructions of the manual provided with the
jack.
●Do not use the jack that was supplied with your vehicle.
●Do not put any part of your body or get underneath the vehicle supported only by
the floor jack.
●Always use floor jack and/or automotive jack stands on a solid, flat, level surface.
●Do not start the hybrid system while the vehicle is supported by the floor jack.
●Stop the vehicle on level firm ground, firmly set the parking brake and put the shift
lever in “P”.
●Make sure to set the floor jack properly at the jack point.
Raising the vehicle with an improperly positioned floor jack will damage the vehi-
cle and may cause the vehicle to fall off the floor jack.
●Do not raise the vehicle while someone is in the vehicle.
●When raising the vehicle, do not place any objects on top of or underneath the
floor jack.
●Lift up the vehicle using a floor jack such as
the one shown in the illustration.

507
4-3. Do-it-yourself maintenance
4
Maintenance and care
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
FuseAmpereCircuit
7AIR SUS20AV S
8PWR OUTLET15Po w e r o u t l e t
9CIG15Cigarette lighter
10ACC7. 5
Audio system, smart access system
with push-button start, touch screen,
rear view monitor system
11IGN10
Smart access system with push-but-
ton start, SRS airbag system, stop-
lights, hybrid system, steering lock
system, electronically controlled
brake system, front passenger occu-
pant classification system ECU
12GAUGE7. 5Gauges and meters
13STR LOCK25Steering lock system
14SECURITY7. 5Smart access system with push-but-
ton start
15TI & TE20Tilt and telescopic steering
16AM17. 5
17STOP SW7. 5Stoplights, shift lock system
18OBD7. 5On-board diagnosis system
19FR P/SEAT RH30Po w e r s e a t

When trouble arises5
521
GS_HV_U (OM30C81U)
January 28, 2010 11:33 am
5-1. Essential information
Emergency flashers............... 522
If your vehicle needs 
to be towed ............................ 523
If you think something is 
wrong ....................................... 531
Event data recorder .............. 5325-2. Steps to take in an 
emergency
If a warning light turns 
on or a warning buzzer 
sounds..................................... 534
If a warning message is 
displayed................................ 543
If you have a flat tire (Vehicles 
with standard tires) ............. 560
If you have a flat tire (Vehicles 
with run-flat tires)................ 570
If the hybrid system will 
not start .................................. 572
If the shift lever cannot be 
shifted from “P”.................... 573
If you lose your keys ............... 574
If the electronic key does not 
operate properly .................. 575
If the 12 volt battery is 
discharged ............................ 578
If your vehicle overheats ...... 581
If the vehicle becomes 
stuck........................................ 584
If your vehicle has to be stopped 
in an emergency .................. 586

5
When trouble arises
541
5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
CAUTION
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly when cold
and inflated to the inflation pressure recommended by the vehicle manufacturer on
the vehicle placard or tire inflation pressure label (tire and load information label).
(If your vehicle has tires of a different size than the size indicated on the vehicle
placard or tire inflation pressure label [tire and load information label], you should
determine the proper tire inflation pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire pressure
monitoring system (TPMS-tire pressure warning system) that illuminates a low tire
pressure telltale (tire pressure warning light) when one or more of your tires is sig-
nificantly under-inflated. Accordingly, when the low tire pressure telltale (tire pres-
sure warning light) illuminates, you should stop and check your tires as soon as
possible, and inflate them to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a substitute for
proper tire maintenance, and it is the driver’s responsibility to maintain correct tire
pressure, even if under-inflation has not reached the level to trigger illumination of
the TPMS low tire pressure telltale (tire pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning system)
malfunction indicator to indicate when the system is not operating properly. The
TPMS (tire pressure warning system) malfunction indicator is combined with the
low tire pressure telltale (tire pressure warning light). When the system detects a
malfunction, the telltale will flash for approximately one minute and then remain
continuously illuminated. This sequence will continue upon subsequent vehicle
start-ups as long as the malfunction exists. When the malfunction indicator is illumi-
nated, the system may not be able to detect or signal low tire pressure as intended.
TPMS (tire pressure warning system) malfunctions may occur for a variety of rea-
sons, including the installation of replacement or alternate tires or wheels on the
vehicle that prevent the TPMS (tire pressure warning system) from functioning
properly. Always check the TPMS (tire pressure warning system) malfunction tell-
tale after replacing one or more tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow the TPMS (tire pressure warning
system) to continue to function properly.

552
5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
Wa r n i n g m e s s a g eDetailsCorrection procedure
(Flashing)
The hybrid battery (trac-
tion battery) is low.
• If a buzzer sounds inter-
mittently, stop the vehicle
in a safe place and shift
lever to P to charge the
hybrid battery (traction
battery).
• If a buzzer sounds con-
tinuously, immediately
stop the vehicle in a safe
place. 
Turn the “POWER”
switch off and then to
ON mode to restart the
hybrid system. Ensuring
the shift lever is in P,
charge the hybrid bat-
tery (traction battery).
(Flashing)
The gasoline engine can-
not operate or the shift
lever is in “N” for a long
time.
Stop the vehicle and shift
the shift lever to “P”.
(Flashing)
The transmission is out of
“P” when attempting to
start the hybrid system.Shift the shift lever to “P”
before pressing the power
switch.

5
When trouble arises
581
5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
If your vehicle overheats
If your hybrid system overheats:
Stop the vehicle in a safe place and turn off the air conditioning
system.
Check to see if steam is coming out from under the hood.
If you see steam: 
Stop the hybrid system. Carefully lift the hood after the
steam subsides and then restart the hybrid system.
If you do not see steam:
Leave the hybrid system operating and carefully lift the
hood.
Remove the engine compartment cover. (P. 4 6 1 )
Check to see if the cooling fan is operating.
If the fan is operating: 
Wait until the engine coolant temperature gauge begins to
fall and then stop the hybrid system.
If the fan is not operating: 
Stop the hybrid system immediately and call your Lexus
dealer.
After the hybrid system has
cooled down sufficiently, check
the coolant level and inspect the
radiator core (radiator) for any
leaks.STEP1
STEP2
STEP3
STEP4
STEP5

584
5-2. Steps to take in an emergency
GS_HV_U (OM30C81U)
October 13, 2015 12:41 pm
If the vehicle becomes stuck
CAUTION
■When attempting to free a stuck vehicle
If you choose to rock the vehicle back and forth to free it, make sure the surround-
ing area is clear, to avoid striking other vehicles, objects or persons. The vehicle
may also lunge forward or lunge back suddenly as it becomes free. Use extreme
caution.
■When shifting the shift lever
Be careful not to shift the shift lever with the accelerator pedal depressed.
This may lead to unexpected rapid acceleration of the vehicle that may cause an
accident and result in death or serious injury.
Carry out the following procedures if the tires spin or the vehicle becomes
stuck in mud, dirt, or snow.
Stop the hybrid system. Set the parking brake and shift the shift
lever in “P”.
Remove the mud, snow, or sand from around the stuck tire.
Place wood, stones or some other material to help provide
traction under the tires.
Restart the hybrid system.
Shift the shift lever to the “D” or “R” position and carefully apply
the accelerator to free the vehicle.
Turn off TRAC/Enhanced VSC if these functions are hampering
your attempts to free the vehicle. (P. 2 1 6 )
STEP1
STEP2
STEP3
STEP4
STEP5