ECU Lexus GS250 2012 Service Manual

1423-2. Opening, closing and locking the doors and trunk
GS350/250_EE (OM30C36E)
Door lock buzzer
If an attempt to lock the doors is made when a door is not fully closed, a
buzzer sounds continuously for 5 seconds. Fully close the door to stop the
buzzer, and lock the vehicle once more.
Security feature
P. 1 2 3
Alarm (if equipped)
Using the wireless remote control to lock the doors will set the alarm system.
(P. 86)
Conditions affecting operation
P. 1 3 0
If the wireless remote control does not operate properly
Locking and unlocking the doors and opening the trunk: Use the mechanical
key.
(P. 821)
Electronic key battery depletion
P. 1 3 4
When the electronic key battery is fully depleted
P. 6 9 5
Confirmation of the registered key number
The number of keys already registered to the vehicle can be confirmed. Ask
any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional for details.
Customization
Settings (e.g. wireless remote control system) can be changed.
(Customizable features: P. 855)

1513-2. Opening, closing and locking the doors and trunk
3
Operation of each component
GS350/250_EE (OM30C36E)Pressing the switch closes the
trunk lid automatically. (A
buzzer sounds.)
Pressing the switch while the trunk
lid is closing opens the trunk lid
again.
The trunk opener switch can be temporarily disabled to protect lug-
gage stored in the trunk against theft.
Turn the main switch in the
glove box off to disable the trunk
opener.
On
Off
The trunk lid cannot be opened
even with the wireless remote con-
trol or the entry function.
Trunk closer switch (vehicles with power trunk lid)
Luggage security system
1
2

1543-2. Opening, closing and locking the doors and trunk
GS350/250_EE (OM30C36E)
CAUTION
Using the trunk
Observe the following precautions.
Failure to do so may cause parts of the body to be caught, resulting in seri-
ous injury.
Remove any heavy loads, such as snow and ice, from the trunk lid before
opening it. Failure to do so may cause the trunk lid to fall closed again
after it is opened.
When opening or closing the trunk lid, thoroughly check to make sure the
surrounding area is safe.
If anyone is in the vicinity, make sure they are safe and let them know that
the trunk is about to open or close.
Use caution when opening or closing the trunk lid in windy weather as it
may move abruptly in strong wind.
Do not attach any accessories other than genuine Lexus parts to the trunk
lid. Such additional weight on the trunk lid may cause the lid to fall closed
again after it is opened.
The trunk lid may fall if it is not opened
fully. It is more difficult to open or
close the trunk lid on an incline than on
a level surface, so beware of the trunk
lid unexpectedly opening or closing by
itself. Make sure that the trunk lid is
fully open and secure before using the
trunk.
When closing the trunk lid, take extra
care to prevent your fingers etc. from
being caught.
When closing the trunk lid, make sure
to press it lightly on its outer surface. If
the trunk handle is used to fully close
the trunk lid, it may result in hands or
arms being ca ght

1553-2. Opening, closing and locking the doors and trunk
3
Operation of each component
GS350/250_EE (OM30C36E)
CAUTION
Trunk easy closer (vehicles with power trunk lid)
Power trunk lid (if equipped)
Observe the following precautions when operating the power trunk lid.
Failure to do so may cause serious injury.
Check the safety of the surrounding area to make sure there are no obsta-
cles or anything that could cause any of your belongings to get caught.
If anyone is in the vicinity, make sure they are safe and let them know that
the trunk is about to open or close.
If the trunk closer switch is pressed while the trunk lid is opening during
automatic operation, the trunk lid stops opening. Take extra care when on
an incline, as the trunk lid may open or close suddenly.
On an incline, the trunk lid may fall after it opens automatically. Make
sure the trunk lid is fully open and secure before using the trunk.
In the following situations, the power trunk lid may detect an abnormality
and automatic operation may be stopped. In this case, the trunk lid has to
be operated manually. Take extra care in this situation, as the stopped
trunk lid may suddenly fall, causing an accident.
• When the trunk lid contacts an obstacle
• When the battery voltage suddenly drops, such as when the engine
switch is turned to IGNITION ON mode or the engine is started during
automatic operation
Do not attach any accessories other than genuine Lexus parts to the trunk
lid. The power trunk lid may not operate, causing itself to malfunction, or
the trunk lid may fall closed again after it is opened.
In the event that the trunk lid is left
slightly open, the trunk easy closer will
automatically close it to the fully closed
position. It takes several seconds before
the trunk easy closer begins to operate.
Be careful not to catch fingers or any-
thing else in the trunk lid, as this may
cause bone fractures or other serious

1934-1. Before driving
4
Driving
GS350/250_EE (OM30C36E)
CAUTION
If you hear a squealing or scraping noise (brake pad wear indicators)
Have the brake pads checked and replaced by any authorized Lexus dealer
or repairer, or another duly qualified and equipped professional as soon as
possible.
Rotor damage may result if the pads are not replaced when needed.
Moderate levels of brake pad and disc wear allow enhanced front braking
power. As a result, the discs may wear more quickly than conventional
brake discs. Therefore, when replacing the brake pads, Lexus recommends
that you also have the thickness of the discs measured.
It is dangerous to drive the vehicle when the wear limits of the brake pads
and/or those of the brake discs are exceeded.
When the vehicle is stopped
Do not race the engine.
If the vehicle is in any gear other than P or N, the vehicle may accelerate
suddenly and unexpectedly, causing an accident.
In order to prevent accidents due to the vehicle rolling away, always keep
depressing the brake pedal while the engine is running, and apply the
parking brake as necessary.
If the vehicle is stopped on an incline, in order to prevent accidents caused
by the vehicle rolling forward or backward, always depress the brake
pedal and securely apply the parking brake as needed.
Avoid revving or racing the engine.
Running the engine at high speed while the vehicle is stopped may cause
the exhaust system to overheat, which could result in a fire if combustible
material is nearby.

1954-1. Before driving
4
Driving
GS350/250_EE (OM30C36E)
CAUTION
When taking a nap in the vehicle
Always turn the engine off. Otherwise, if you accidentally move the shift
lever or depress the accelerator pedal, this could cause an accident or fire
due to engine overheating. Additionally, if the vehicle is parked in a poorly
ventilated area, exhaust gases may collect and enter the vehicle, leading to
death or a serious health hazard.
When braking
When the brakes are wet, drive more cautiously.
Braking distance increases when the brakes are wet, and this may cause
one side of the vehicle to brake differently than the other side. Also, the
parking brake may not securely hold the vehicle.
If the power brake assist function does not operate, do not follow other
vehicles closely and avoid hills or sharp turns that require braking.
In this case, braking is still possible, but the brake pedal should be
depressed more firmly than usual. Also, the braking distance will
increase.
The brake system consists of 2 individual hydraulic systems; if one of the
systems fails, the other will still operate. In this case, the brake pedal
should be depressed more firmly than usual and the braking distance will
increase.
If this happens, do not continue to drive the vehicle. Have your brakes
fixed immediately.
If the vehicle becomes stuck
Do not spin the wheels excessively when any of the tires is up in the air, or
the vehicle is stuck in sand, mud, etc. This may damage the driveline com-
ponents or propel the vehicle forward or backward, causing an accident.

1984-1. Before driving
GS350/250_EE (OM30C36E)
Cargo and luggage
Take notice of the following information about storage precau-
tions, cargo capacity and load:
CAUTION
Things that must not be carried in the trunk
The following things may cause a fire if loaded in the trunk:
Receptacles containing gasoline
Aerosol cans
Storage precautions
Observe the following precautions.
Failure to do so may prevent the pedals from being depressed properly, may
block the driver’s vision, or may result in items hitting the driver or passen-
gers, possibly causing an accident.
Stow cargo and luggage in the trunk whenever possible.
Do not place cargo or luggage in or on the following locations.
• At the feet of the driver
• On the front passenger or rear seats (when stacking items)
• On the package tray
• On the instrument panel
• On the dashboard
• In front of the Remote Touch screen
Secure all items in the occupant compartment.
Load and distribution
Do not overload your vehicle.
Do not apply loads unevenly.
Improper loading may cause deterioration of steering or braking control
which may cause death or serious injury.

2044-1. Before driving
GS350/250_EE (OM30C36E)
Tire information
Increase the tire inflation pressure to 20.0 kPa (0.2 kgf/cm2 or bar, 3 psi)
greater than the recommended value when towing. (P. 850)
Increase the air pressure of the trailer tires in accordance with the total
trailer weight and according to the values recommended by the manufac-
turer of your trailer.
Break-in schedule
Lexus recommends that vehicles fitted with new power train components
should not be used for towing trailers for the first 800 km (500 miles).
Safety checks before towing
Check that the maximum load limit for the towing hitch/bracket hitch ball is
not exceeded. Bear in mind that the coupling weight of the trailer will add
to the load exerted on the vehicle. Also make sure that you will not be tow-
ing a load that exceeds the maximum permissible axle capacity.
Ensure that the trailer load is secure.
Supplementary outside rear view mirrors should be added to the vehicle if
the traffic behind cannot be clearly seen with standard mirrors. Adjust the
extending arms of these mirrors on both sides of the vehicle so that they
always provide maximum visibility of the road behind.
Maintenance
Maintenance must be performed more frequently when using the vehicle
for towing due to the greater weight burden placed on the vehicle compared
to normal driving.
Retighten all bolts securing the hitching ball and bracket after towing for
approximately 1000 km (600 miles).

2064-1. Before driving
GS350/250_EE (OM30C36E)
Increasing vehicle-to-vehicle distance
At a speed of 10 km/h (6 mph), the distance to the vehicle run-
ning ahead of you should be equivalent to or greater than the
combined length of your vehicle and trailer. Avoid sudden brak-
ing that may cause skidding. Otherwise, the vehicle may spin out
of control. This is especially true when driving on wet or slippery
road surfaces.
Sudden acceleration/steering input/cornering
Executing sharp turns when towing may result in the trailer col-
liding with your vehicle. Decelerate well in advance when
approaching turns and take them slowly and carefully to avoid
sudden braking.
Important points regarding turning
The wheels of the trailer will travel closer to the inside of the
curve than the wheels of the vehicle. To make allowance for this,
take the turns wider than you would normally do.
Important points regarding stability
Vehicle movement resulting from uneven road surfaces and
strong crosswinds will affect handling. The vehicle may also be
rocked by passing buses or large trucks. Frequently check behind
when moving alongside such vehicles. As soon as such vehicle
movement occurs, immediately start to decelerate smoothly by
slowly applying the brakes. Always steer the vehicle straight
ahead while braking.
Passing other vehicles
Consider the total combined length of your vehicle and trailer
and ensure that the vehicle-to-vehicle distance is sufficient
before executing lane changes.
Transmission information
To maintain engine braking efficiency, when using engine brak-
ing, when driving on a long steep downgrade, do not use the

2114-2. Driving procedures
4
Driving
GS350/250_EE (OM30C36E)
Auto power off function
If the vehicle is left in ACCESSORY mode for more than 20 minutes or
IGNITION ON mode (the engine is not running) for more than an hour with
the shift lever in P, the engine switch will automatically turn off. However,
this function cannot entirely prevent battery discharge. Do not leave the vehi-
cle with the engine switch in ACCESSORY or IGNITION ON mode for long
periods of time when the engine is not running.
Electronic key battery depletion
P. 1 3 4
Conditions affecting operation
P. 1 3 0
Notes for the entry function
P. 1 3 1
If the engine does not start
The engine immobilizer system may not have been deactivated. (P. 8 0 )
Contact any authorized Lexus dealer or repairer, or another duly qualified
and equipped professional.
Check that the shift lever is securely set in P. The engine may not start if the
shift lever is displaced out of P. “Shift to P position to Start” will be dis-
played on the multi-information display.
Steering lock
After turning the engine switch off and opening and closing the doors, the
steering wheel will be locked due to the steering lock function. Operating the
engine switch again automatically cancels the steering lock.