2021 LEXUS LS500 jump start

4447-2. Steps to take in an emergency
■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.177)
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.
Method connecting jumper (or
booster) cables to the battery
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.67)
2 Open the trunk lid and remove the
luggage mat. ( P.349)
In the event that the trunk opener cannot
be used, use the mechanical key to open
the trunk. (P.442)
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

4457-2. Steps to take in an emergency
7
When trouble arises
3Connect 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)
Negative (-) battery terminal (your vehicle)
4 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.
5 Open and close any of the doors of
your vehicle with the engine switch
off.
6 Maintain the engine speed of the
second vehicle and start the engine
of your vehicle by turning the
engine switch to IGNITION ON
mode.
7 Once the vehicle’s engine has
started, remove the jumper cables
in the exact reverse order from
which they were connected.
Method connecting jumper (or
booster) cables to the exclusive
jump starting terminal
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.67)
2 Open the hood. Remove the ser-
vice cover. ( P.381, 385)
3 Open the fuse box cover.
A
B
C
D
A
B
C
D

4467-2. Steps to take in an emergency
Push the tab in and lift the lid off.4Open the exclusive jump starting
terminal cover.
5 Remove the engine cover.
(P.384)
6 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 .
Exclusive jump starting terminal (your vehicle)
Positive (+) battery terminal (second vehicle)
Negative (-) battery terminal (second vehicle)
Solid, stationary, unpainted metallic point away from the exclusive jump starting
terminal and any mo ving parts as shown in the illustration
7 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.
A
B
C
D
A
B
C
D

4477-2. Steps to take in an emergency
7
When trouble arises
8Open and close any of the doors of
your vehicle with the engine switch
off.
9 Maintain the engine speed of the
second vehicle and start the engine
of your vehicle by turning the
engine switch to IGNITION ON
mode.
10 Once the vehicle’s engine has
started, remove the jumper cables
in the exact reverse order from
which they were connected.
11 Close the exclusive jump starting
terminal cover, and reinstall the fuse
box cover to its original position.
12 Install the service cover. ( P.385)
13 Install the engine cover. ( P.385)
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.
■When the battery is removed or dis-
charged
●Information stored in the ECU is cleared.
When the battery is depleted, have the
vehicle inspected at your Lexus dealer.
●Some systems may require initialization.
(  P.490)
■When removing the battery terminals
When the battery terminals are removed,
the information stored in the ECU is
cleared. Before removi ng the battery termi-
nals, contact your Lexus dealer.
■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 disconnecting the bat-
tery, turn the engine switch off.
If you are unsure wh at mode the engine
switch was in before the battery dis-
charged, be especially careful when
reconnecting the battery.
■When replacing the battery
●Use a Central Degassing type battery
(European Regulations).
●Use a battery with the same case size as
the previous battery and an equivalent
20 hour rate capacity (20HR) 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, the battery may dis-
charge and the engine may not be able to
start.

4497-2. Steps to take in an emergency
7
When trouble arises
1Stop the vehicle in a safe place and
turn off the air conditioning system,
and then stop the engine.
2 If you see steam:
Carefully lift the hood after the
steam subsides.
If you do not see steam:
Carefully lift the hood.
3 After the engine has cooled down
sufficiently, inspect the hoses and
WARNING
■After recharging the battery
Have the battery inspected at your Lexus
dealer as soon as possible.
If the battery is dete riorating, continued
use may cause the battery to emit a mal-
odorous gas, which may be detrimental
to the health of passengers.
■When replacing the battery
●When the vent plug and indicator are
close to the hold down clamp, the bat-
tery fluid (sulfuric acid) may leak.
●For information regarding battery
replacement, contact your Lexus
dealer.
●After replacing, securely attach the
exhaust hose and exhaust hole plug to
the exhaust hole of the replaced bat-
tery. If not properly installed, gases
(hydrogen) may leak into the vehicle
interior, and there is the possible dan-
ger of the gas igniting and exploding.
NOTICE
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entan-
gled in the cooling fan or engine drive
belt.
■To prevent damaging the vehicle
The exclusive jump starting terminal is to
be used when charging the battery from
another vehicle in an emergency. It can-
not be used to jump start another vehicle.
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
 The engine coolant temperature
gauge ( P.75, 78) is in the red
zone or a loss of engine power is
experienced. (For example, the
vehicle speed does not increase.)
 “Engine Coolant Temp High Stop
in a Safe Place See Owner’s
Manual” is shown on the
multi-information display.
 Steam comes out from under the
hood.
Correction procedures