Page 529 of 665
528
4-3. Do-it-yourself maintenance
4RUNNER_U
Wireless remote control/electronic key batter y
Replace the battery with a new one if it is depleted.
■You will need the following items:
●Flathead screwdriver
● Lithium battery CR2016 (vehicles without a smart key sys-
tem), or CR1632 (vehicles with a smart key system)
■ Replacing the battery (vehicles without a smart key system)
Remove the cover.
To prevent damage to the key,
cover the tip of the screwdriver
with a rag.
Remove the module.
Open the case cover using a
coin protected with tape etc.
and remove the depleted bat-
tery.
Insert a new battery with the
“+” terminal facing up.
STEP 1
STEP 2
STEP 3
Page 530 of 665
529
4-3. Do-it-yourself maintenance
4
Maintenance and care
4RUNNER_U
■
Replacing the battery (vehicles with a smart key system)
Take out the mechanical key.
Remove the cover.
To prevent damage to the key,
cover the tip of the screwdriver
with a rag.
Remove the depleted battery.
Insert a new battery with the
“+” terminal facing up.
STEP 1
STEP 2
STEP 3
Page 531 of 665

530 4-3. Do-it-yourself maintenance
4RUNNER_U
■Use a CR2016 (vehicles without a smart key system) or CR1632 (vehi-
cles with a smart key system) lithium battery
● Batteries can be purchased at your Toyota dealer, local electrical appli-
ance shops or camera stores.
● Replace only with the same or equivalent type recommended by the
manufacturer.
● Dispose of used batteries according to local laws.
■ If the key battery is depleted
The following symptoms may occur:
● The smart key system and wireless remote control will not function prop-
erly.
● The operational range will be reduced.
CAUTION
■Removed battery and other parts
Keep away from children.
These parts are small and if swallowed by a child, they can cause choking.
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents:
● Always work with dry hands.
Moisture may cause the battery to rust.
● Do not touch or move any other component inside the remote control.
● Do not bend either of the battery terminals.
Page 554 of 665
When trouble arises5
553
4RUNNER_U
5-1. Essential informationEmergency flashers ......... 554
If your vehicle needs to be towed ........................ 555
If you think something is wrong ......................... 561
Fuel pump shut off system ........................... 562
Event data recorder ......... 563
5-2. Steps to take in an emergency
If a warning light turns on or a warning buzzer
sounds ........................... 565
If you have a flat tire......... 578
If the engine will not start ................................ 590
If the shift lever cannot be shifted from P ............ 592
If you lose your keys ........ 594
If you cannot operate back door opener ........... 595
If the electronic key does not operate properly
(vehicles with a smart
key system) .................... 596
If the vehicle battery is discharged ..................... 598
If your vehicle overheats ....................... 603
If the vehicle becomes stuck .............................. 606
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5
When trouble arises
571
5-2. Steps to take in an emergency
4RUNNER_U
*: If the engine does not start when the electronic key is inside the vehi-
cle, the electronic key battery may be depleted or there may be diffi-
culties receiving the si gnal from the key. (
P. 4 1)
ContinuousContinuous
Smart key system warning
light
Indicates that the driver’s
door has been opened and
closed with the shift lever not
in P, the “ENGINE START
STOP” switch in any mode
other than off and the elec-
tronic key has been taken out
of the detection area • Shift the shift
lever to P.
• Confirm the location of the
electronic
key.
Once
Sounds
for 10
seconds
(Remains on for 60
seconds) Smart key system warning
light
Indicates that the electronic
key has been taken out of
the vehicle and an attempt
was made to lock the doors
with the “ENGINE START
STOP” switch in any mode
other than off Turn the
“ENGINE
START
STOP” switch
off and lock
the doors
again.
Once
Smart key system warning
light
Indicates that an attempt was
made to drive when the elec-
tronic key was not present Confirm the
location of the
electronic
key.
Interior
buzzerExterior
buzzerWarning
lightWarning light/DetailsCorrection procedure
Page 592 of 665

5
When trouble arises
591
5-2. Steps to take in an emergency
4RUNNER_U
Emergency start function (vehicles with a smart key system)
When the engine does not start, the following steps can be used as
an interim measure to start the engine if the “ENGINE START STOP”
switch is functioning normally: Set the parking brake.
Shift the shift lever to P.
Turn the “ENGINE START STOP” switch to ACCESSORY
mode.
Press and hold the “ENGINE START STOP” switch for about
15 seconds while depressing the brake pedal firmly.
Even if the engine can be start ed using the above steps, the system
may be malfunctioning. Have the vehicle inspected by your Toyota
dealer.
■ The starter motor does not turn over, the interior lights and
headlights do not turn on, or the horn does not sound.
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. 598)
● There may be a malfunction in the steering lock system. (vehi-
cles with a smart key system)
Contact your Toyota dealer if the problem cannot be repaired, or if
repair procedures are unknown.
STEP 1
STEP 2
STEP 3
STEP 4
Page 597 of 665
596
5-2. Steps to take in an emergency
4RUNNER_U
If the electronic key does not operate properly (vehicles with a smar t key system)
Locking and unlocking the doorsUse the mechanical key (P.
31) in order to perform the fol-
lowing operations:
Locks all doors
Unlocks all doors
Turning the key rearward
unlocks the driver’s door.
Turning the key once again
unlocks the other doors.
If communication between the electronic key and vehicle is inter-
rupted ( P. 41) or the electronic key cannot be used because the
battery is depleted, the smart key system and wireless remote con-
trol cannot be used. In such cases, the doors can be opened and the
engine can be started by following the procedure below.
CTH52AS001
Page 598 of 665

5
When trouble arises
597
5-2. Steps to take in an emergency
4RUNNER_U
Changing “ENGINE START STOP”
switch modes and starting the
engine
Ensure that the shift lever is in P and depress the brake pedal. Touch the Toyota emblem side of
the electronic key to the
“ENGINE START STOP” switch.
If any of the doors is opened or
closed while the key is being
touched to the switch, an alarm
will sound to indicate that the start
function cannot detect the key.
To change “ENGINE START STOP” switch modes: Within 10
seconds of the buzzer soundin g, release the brake pedal and
press the “ENGINE START STOP” switch. Modes can be
changed each time the sw itch is pressed. (P. 168)
To start the engine: Press the “ENGINE START STOP” switch
within 10 seconds of the buz zer sounding, keeping the brake
pedal depressed.
In the event that the “ENGINE ST ART STOP” switch cannot be oper-
ated, contact your Toyota dealer.
STEP 1
CTH52AS002
STEP 2
■ Stopping the engine
Shift the shift lever to P and press the “ENGINE START STOP” 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. 529)
STEP 3