Page 569 of 660
5698-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
NOTICE
■Be careful when driving over bumps with the compact spare tire installed on the vehi-
cle
When driving with the compact spare tire installed, the vehicle height will be different
than when driving with standard tires. Be careful when driving over uneven road sur-
faces, etc.
■Driving with tire chains and the compact spare tire
Do not fit tire chains to the compact spare tire.
Tire chains may damage the vehicle body and adversely affect driving performance.
■When replacing the tires
When removing or fitting the wheels, tires or the tire pressure warning valve and trans-
mitter, contact your Lexus dealer as the tire pressure warning valve and transmitter
may be damaged if not handled correctly.
Page 570 of 660

5708-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
One of the following may be the cause of the problem:
●There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle.
●The engine may be flooded.
Try to restart the engine again following correct starting procedures.
( P. 186)
●There may be a malfunction in th e engine immobilizer system. (P. 76)
One of the following may be the cause of the problem:
●The battery terminal connections may be loose or corroded.
●The battery may be discharged. ( P. 575)
The engine starting system may be malfun ctioning due to an electrical problem
such as electronic key battery depletio n or a blown fuse. However, an interim
measure is available to start the engine. ( P. 571)
If the engine will not start
If the engine will not start even though correct starting procedures are being
followed ( P. 186), consider each of the following points:
The engine will not start even thoug h the starter motor operates nor-
mally.
The starter motor turns over slowly , the interior lights and headlights
are dim, or the horn does not sound or sounds at a low volume.
The starter motor does not turn over
Page 571 of 660

5718-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
One of the following may be the cause of the problem:
●One or both of the battery terminals may be disconnected.
●The battery may be discharged. (P. 575)
●There may be a malfunction in the steering lock system.
Contact your Lexus dealer if the problem cannot be repaired, or if repair procedures
are unknown.
When the engine does not start, the follo wing steps can be used as an interim
measure to start the engine if the engine switch is functioning normally:
Set the parking brake.
Shift the shift lever to P.
Turn the engine switch to ACCESSORY mode.
Press and hold the engine switch for about 15 seconds while depressing the
brake pedal firmly.
Even if the engine can be started using the above steps, the system may be mal-
functioning. Have the vehicle in spected by your Lexus dealer.
The starter motor does not turn over, the interior lights and headlights
do not turn on, or the horn does not sound.
Emergency start function
1
2
3
4
Page 572 of 660

5728-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
■Doors
Use the mechanical key (P. 119) in
order to perform the following oper-
ations:
Locks all the doors
Closes the windows and moon
roof (turn and hold)
*
Unlocks the door
Turning the key rearward unlocks the
driver’s door. Turning the key once
again within 5 seconds unlocks the
other doors.
Opens the windows and moon roof (turn and hold)*
*
: This setting must be custom ized at your Lexus dealer.
■Trunk
Turn the mechanical key clockwise
to open. (P. 79)
If the electronic key does not operate properly
If communication between the electron ic key and vehicle is interrupted (P.
137) or the electronic key cannot be us ed because the battery is depleted, the
smart access system with push-button st art and wireless remote control can-
not be used. In such cases, the doors and trunk can be opened and the engine
can be started by follow ing the procedure below.
Locking and unlocking the doors, unlocking the trunk and key linked
functions
1
2
3
4
Page 573 of 660
5738-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side of the
electronic key to the engine switch.
When the electronic key is detected, a
buzzer sounds and the engine switch
will turn to IGNITION ON mode.
When the smart access system with
push-button start is deactivated in cus-
tomization setting, the engine switch will
turn to ACCESSORY mode.
Firmly depress the brake pedal and check that is shown on the multi-
information display.
Press the engine switch.
In the event that the engine still cannot be started, contact your Lexus dealer.
Starting the engine
1
2
3
4
Page 574 of 660

5748-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
■Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when stopping
the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. ( P. 502)
■Changing engine switch modes
Release the brake pedal and press the engine switch in step above.
The engine does not start and modes will be changed each time the switch is pressed.
( P. 187)
■When the electronic key does not work properly
●Make sure that the smart access system wi th push-button start has not been deacti-
vated in the customization setting. If it is off, turn the function on.
(Customizable features: P. 613)
●Check if battery-saving mode is set. If it is set, cancel the function. ( P. 136)
WARNING
■When using the mechanical key and operating the power windows or moon roof
Operate the power window or moon roof after checking to make sure that there is no
possibility of any passenger having any of their body parts caught in the window or
moon roof.
Also, do not allow children to operate the mechanical key. It is possible for children and
other passengers to get caught in the power window or moon roof.
3
Page 575 of 660
5758-2. Steps to take in an emergency
8
When trouble arises
IS350 AWD/IS350/IS300 AWD/IS300_U
If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt
battery, you can jump start your vehicle by following the steps below.
Confirm that the electronic key is
being carried.
When connecting the jumper (or
booster) cables, depe nding on the situa-
tion, the alarm may activate and doors
locked. (
P. 79)
Open the hood ( P. 470)
If the vehicle battery is discharged
The following procedures may be used to start the engine if the vehicle’s bat-
tery is discharged.
You can also call your Lexus deal er or a qualified repair shop.
1
2
Page 576 of 660
5768-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
Connect the jumper cables according to the following procedure:
IS350 AWD/IS350/IS300 AWD
IS300
Connect a positive jumper cable clamp to the positive (+) battery terminal
on your vehicle.
Connect the clamp on the other end of the positive cable to the positive (+)
battery terminal on the second vehicle.
Connect a negative cable clamp to the negative (-) battery terminal on the
second vehicle.
Connect the clamp at the other end of th e negative cable to a solid, station-
ary, unpainted metallic po int away from the battery and any moving parts,
as shown in the illustration.
Start the engine of the second vehicle. Increase the engine speed slightly and
maintain at that level for approximatel y 5 minutes to recharge the battery of
your vehicle.
Open and close any of the doors of your vehicle with the engine switch off.
3
1
2
3
4
4
5