jump start LEXUS RCF 2021 Owners Manual

3347-2. Steps to take in an emergency
key when the alarm system is set, the alarm
may be triggered.
■Changing engine switch modes
Release the brake pedal and press the
engine switch in step 3 above.
The engine does not start and modes will be
changed each time the switch is pressed.
(  P.130)
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.
1 Confirm that the electronic key is
being carried.
When connecting the jumper (or booster)
cables, depending on the situation, the
alarm may activate and doors locked.
( P.59)
2 Open the hood. ( P.264)
3 Remove the engine cover.
Raise the rear of the engine cover
to remove the rear clip, and then
If the vehicle battery is dis-
charged
The following procedures may be
used to start the engine if the vehi-
cle’s battery is discharged.
You can also call your Lexus dealer
or a qualified repair shop.
Restarting the engine

3357-2. Steps to take in an emergency
7
When trouble arises
raise the front of the engine cover
to remove the front clips.
4 Connect a positive jumper cable clamp to on your vehicle and connect the
clamp on the other end of the positive cab le to on the second vehicle. Then,
connect a negative cable clamp to on the second vehicle and connect the
clamp at the other end of the negative cable to .
Positive (+) battery terminal (your vehicle)
Positive (+) battery terminal (second vehicle)
Negative (-) battery terminal (second vehicle)
Solid, stationary, unpainted metallic poin t away from the battery and any mov-
ing parts as shown in the illustration
5 Start the engine of the second vehi-
cle. Increase the engine speed
slightly and maintain at that level for
approximately 5 minutes to
recharge the battery of your vehi-
cle.
6 Open and close any of the door of
your vehicle with the engine switch
off. 7
Maintain the engine speed of the
second vehicle and start the engine
of your vehicle by turning the
engine switch to IGNITION ON
mode.
8 Once the vehicle’s engine has
started, remove the jumper cables
in the exact reverse order from
which they were connected.
A
B
C
D
A
B
C
D

3367-2. Steps to take in an emergency
Once the engine starts, have the vehi-
cle inspected at your Lexus dealer as
soon as possible.
■Starting the engine when the battery is
discharged
The engine cannot be started by push-start-
ing.
■To prevent battery discharge
●Turn off the headlights and the audio sys-
tem while the engine is off.
●Turn off any unnecessary electrical com-
ponents when the vehicle is running at a
low speed for an extended period, such
as in heavy traffic.
■Charging the battery
The electricity stored in the battery will dis-
charge gradually even when the vehicle is
not in use, due to natural discharge and the
draining effects of certain electrical appli-
ances. If the vehicle is left for a long time,
the battery may discharge, and the engine
may be unable to start. (The battery
recharges automatically during driving.)
■When recharging or replacing the bat-
tery
●In some cases, it may not be possible to
unlock the doors using the smart access
system with push-button start when the
battery is discharged. Use the wireless
remote control or the mechanical key to
lock or unlock the doors.
●The engine may not start on the first
attempt after the battery has recharged
but will start normally after the second
attempt. This is not a malfunction.
●The engine switch mode is memorized by
the vehicle. When the battery is recon-
nected, the system will return to the
mode it was in before the battery was dis-
charged. Before di sconnecting the bat-
tery, turn the engine switch off.
If you are unsure what mode the engine
switch was in befo re the battery dis-
charged, be especially careful when
reconnecting the battery.
■When replacing the battery
●Use a battery that conforms to European
regulations.
●Use a battery that tha case size is same as
the previous one (LN3), 20 hour rate
capacity (20HR) is equivalent (70Ah) or
greater, and performance rating (CCA)
is equivalent (592A) or greater.
• If the sizes differ, the battery cannot be properly secured.
• If the 20 hour rate capacity is low, even if the time period where the vehicle is not
used is a short time, battery may dis-
charge and the engine may not be able to
start.
●For details, consult your Lexus dealer.
WARNING
■Avoiding battery fires or explosions
Observe the following precautions to
prevent accidentally igniting the flamma-
ble gas that may be emitted from the bat-
tery:
●Make sure each jumper cable is con-
nected to the correct terminal and that
it is not unintentionally in contact with
any other than the intended terminal.
●Do not allow the other end of the
jumper cable connected to the “+” ter-
minal to come into contact with any
other parts or meta l surfaces in the
area, such as brackets or unpainted
metal.
●Do not allow the + and - clamps of the
jumper cables to come into contact
with each other.
●Do not smoke, use matches, cigarette
lighters or allow open flame near the
battery.
■Battery precautions
The battery contains poisonous and cor-
rosive acidic electrol yte, while related
parts contain lead and lead compounds.
Observe the following precautions when
handling the battery: