2018 LEXUS RCF Owners Manual

5217-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U) 7
When trouble arises WARNING ■
When using the mechanical key and operating the power windows or moon roof
Operate the power window or moon roof afte r 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 op erate the mechanical key. It is possible for children and
other passengers to get caught in the power window or moon roof.

522 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)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. 81)
Open the hood. (  P. 393)
Remove the engine cover. (RC F)
Raise the front of the engine cover to
remove the front clips, and then raise
the rear of the engine cover to
remove the rear clips.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
3

5237-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U) 7
When trouble arises Connect the jumper cables accordin g to the following procedure:
RC350/RC300 AWD 
RC300 
RC F
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. 4
1
2
3
4

524 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)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 door of your vehicle with the engine switch off.
Maintain the engine speed of the second vehicle and start the engine of your
vehicle by turning the engine switch to IGNITION ON mode.
Once the vehicle’s engine has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the engine starts, have the vehicle inspected at your Lexus dealer as soon
as possible. ■
Starting the engine when the battery is discharged
The engine cannot be started by push-starting. ■
To prevent battery discharge ●
Turn off the headlights and the audio system while the engine is off. ●
Turn off any unnecessary electrical componen ts 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 disc harge gradually even when the vehicle is not
in use, due to natural discharge and the draini ng effects of certain electrical appliances. 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 battery ●
In some cases, it may not be possible to un lock 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 discharged.
Before disconnecting the battery, turn the engine switch off.
If you are unsure what mode the engine switch was in before the battery discharged, be
especially careful when reconnecting the battery. 5
6
7
8

5257-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U) 7
When trouble arises WARNING ■
Avoiding battery fires or explosions
Observe the following precautions to preven t accidentally igniting the flammable gas
that may be emitted from the battery: ●
Make sure each jumper cable is connected 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 cab le connected to the “+” terminal to come
into contact with any other parts or metal surfaces in the area, such as brackets or
unpainted metal. ●
Do not allow the + and - clamps of the jump er cables to come in to 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 corrosive acidic electrolyte, while related parts
contain lead and lead compounds. Observ e the following precautions when handling
the battery: ●
When working with the battery, always wear safety glasses and take care not to allow
any battery fluids (acid) to come into cont act with skin, clothing or the vehicle body.●
Do not lean over the battery. ●
In the event that battery fluid comes into contact with the skin or eyes, immediately
wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention can be
received. ●
Always wash your hands afte r handling the battery support, terminals, and other bat-
tery-related parts. ●
Do not allow childre n near the battery.
NOTICE ■
When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in the
cooling fans or engine drive belt.

526 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)●
The engine coolant temperature gauge (  P. 91, 96) 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.
Stop the vehicle in a safe place and tu rn off the air conditioning system, and
then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.If your vehicle overheats The following may indicate that your vehicle is overheating.
Correction procedures 1
2

5277-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U) 7
When trouble arises After the engine has cooled down suff iciently, inspect th e hoses and radiator
core (radiator) for any leaks.
Radiator
Cooling fans If a large amount of coolant leaks, immediately contact your Lexus dealer. 3
1
2
RC350/RC300 AWD 
RC300
RC F

528 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)The coolant level is satisfactory if it is between the full (“FULL” or “F”) and low
(“LOW” or “L”) lines on the reservoir.
Reservoir cap
“FULL” or “F”
“LOW” or “L” 4
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3
Engine (RC350/RC300 AWD) 
Engine (RC300)
Engine (RC F) 
Intercooler (RC300)