2018 LEXUS RC300 check engine

5297-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U) 7
When trouble arises Add coolant if necessary. Water can be used in an emerge ncy if coolant is unavailable.
Start the engine and turn the air conditio ning system on to check that the radi-
ator cooling fans operate and to check for coolant leaks from the radiator or
hoses. The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air flow.
If it is difficult to check these, turn the air conditioning system on and off repeatedly.
(The fan may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately an d contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer. 5 
Engine (RC350/RC300 AWD) 
Engine (RC300)
Engine (RC F) 
Intercooler (RC300)
6
7

540 8-1. Specifications
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)■
Oil capacity (Drain and refill [Reference
* ])
* : The engine oil capacity is a reference quantity to be used when changing the engine
oil. Warm up and turn off the engine, wait more than 5 minutes, and check the oil level
on the dipstick.Fuel Fuel type Unleaded gasoline only
Octane Rating 91 (Research Octane Number 96) or higher
Fuel tank capacity
(Reference) 17.5 gal. (66.3 L, 14.6 Imp. gal.)
Lubrication system With filter Without filter
RC350 6.0 qt. (5.7 L, 5.0 Imp. qt.) 5.8 qt. (5.5 L, 4.8 Imp. qt.)
RC350 AWD/
RC300 AWD 6.8 qt. (6.4 L, 5.6 Imp. qt.) 6.3 qt. (6.0 L, 5.3 Imp. qt.)
RC300 4.9 qt. (4.6 L, 4.0 Imp. qt.) 4.5 qt. (4.3 L, 3.8 Imp. qt.)
RC F 9.3 qt. (8.8 L, 7.7 Imp. qt.) 8.3 qt. (7.9 L, 7.0 Imp. qt.)

5458-1. Specifications
8
Vehicle specifications
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)* : The fluid capacity is a reference quantity.
If replacement is necessary, contact your Lexus dealer.Electrical system Battery
Open voltage at 68  F
(20  C): 12.3 V or higher
If the voltage is lower than the standard value, charge
the battery.
(Voltage is checked 20 minutes after the engine and all
lights are turned off.)
Charging rates 5 A max.
Automatic transmission Fluid capacity
* RC350 10.0 qt. (9.5 L, 8.4 Imp. qt.)
RC350AWD/RC300
AWD 10.6 qt. (10.0 L, 8.8 Imp. qt.)
RC300 9.2 qt. (8.7 L, 7.7 Imp. qt.)
RC F 11.8 qt. (11.2 L, 9.9 Imp. qt.)
Fluid type Toyota Genuine ATF WS
NOTICE ■
Automatic transmission fluid type
Using transmission fluid other than “Toyota Genuine ATF WS” may cause deterioration
in shift quality, locking up of your transm ission accompanied by vibration, and ulti-
mately damage the transmission of your vehicle.
Front differential (AWD models) Oil capacity 0.74 qt. (0.70 L, 0.61 Imp. qt.)
Oil type and viscosity Hypoid gear oil API GL-5
Above 0  F (-18  C): SAE90
Below 0  F (-18  C): SAE80W or SAE80W-90

612
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)What to do if... (Troubleshooting)
What to do if... (Troubleshooting) ●
If you lose your mechanical keys, ne w genuine mechanical keys can be made
by your Lexus dealer. (  P. 142)●
If you lose your electronic keys, the risk of vehicle theft increases significantly.
Contact your Lexus dealer immediately. (  P. 144)●
Is the electronic key battery weak or depleted? (  P. 427)●
Is the engine switch in IGNITION ON mode?
When locking the doors, turn the engine switch off. (  P. 208)●
Is the electronic key left inside the vehicle?
When locking the doors, make sure that you have the electronic key on your
person. ●
The function may not operate properly du e to the condition of the radio wave.
(  P. 158)
●
The function to prevent the electronic key from being left inside the trunk will
operate and you can open th e trunk as usual. Take the key out from the trunk.
(  P. 153)If you have a problem, check the foll owing before contacting your Lexus
dealer.
The doors cannot be locked, unlocked, opened or closed You lose your keys
The doors cannot be locked or unlocked
The trunk lid is closed with the electronic key left inside

614 What to do if... (Troubleshooting)
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)●
The seat belt reminder light is flashing
Are the driver and the front passe nger wearing the seat belts? (  P. 455)●
The parking brake indicator is on
Is the parking brake released? (  P. 222)
Depending on the situation, other type s of warning buzzer may also sound.
(  P. 453, 460)
●
Did anyone inside the vehicle open a door during setting the alarm?
The sensor detects it and the alarm sounds. (  P. 80)
Do one of the following to de activate or stop the alarms:• Unlock the doors.
• Open the trunk using the entry function or wireless remote control.
• Turn the engine switch to ACCESSORY or IGNITION ON mode, or start the
engine.
●
Is the electronic key left inside th e vehicle or the moon roof opened?
Check the message on the multi-information display. (  P. 460)
●
When a warning light turns on or a wa rning message is displayed, refer to
P. 453, 460. A warning buzzer sounds during driving
An alarm is activated and the horn sounds
A warning buzzer sounds when leaving the vehicle
A warning light turns on or a warning message is displayed

621Alphabetical index
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)Emergency, in case of
If a warning buzzer sounds...........453
If a warning light turns on...............453
If a warning message
is displayed ....................................... 460
If the electronic key
does not operate properly ......... 518
If the engine will not start................. 516
If the vehicle battery is
discharged ......................................... 522
If you have a flat tire .............489, 502
If you think something
is wrong................................................ 451
If your vehicle becomes stuck .....532
If your vehicle has to be
stopped in an emergency ..........443
If your vehicle needs
to be towed ....................................... 444
If your vehicle overheats ................526
Engine ....................................................... 539
ACCESSORY mode..................... 208
Compartment......................................397
Engine switch .......................................207
Hood ........................................................393
How to start the engine ..................207
Identification number ...................... 538
If the engine will not start................. 516
Ignition switch (engine switch)....207
Overheating .........................................526 Engine coolant ...................................... 404
Capacity................................................. 544
Checking ............................................... 404
Preparing and checking
before winter ........................320, 320
Engine coolant temperature
gauge ..................................................91, 96
Engine immobilizer system .................. 79
Engine oil ................................................. 400
Capacity.................................................540
Checking .............................................. 400
Preparing and checking
before winter ........................320, 320
Engine oil maintenance data ........... 403
Engine oil temperature gauge............96
Engine switch ..........................................207
Enhanced VSC ....................................... 312
EPS (Electric Power Steering) ......... 313
Warning light ....................................... 454
Event data recorder (EDR)................... 10
Expert mode ............................................ 316

623Alphabetical index
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)Garage door opener .......................... 359
Gauges ................................................. 91, 96
Glove box ................................................. 351
Glove box light ....................................... 351
Head restraints ......................................... 171
Headlight cleaner................................. 233
Headlights ............................................... 225
Automatic High Beam
system ..................................................228
Light switch ........................................... 225
Replacing light bulbs ........................439
Heaters
Air conditioning system ..................333
Heated steering wheel ....................344
Outside rear view mirrors ............ 338
Seat heaters ..........................................345
Hill-start assist control ..........................312
Hood .......................................................... 393
Open ........................................................393
Hooks
Cargo hooks ....................................... 353
Coat hooks .......................................... 358
Retaining hooks (floor mat) .............30
Horn ............................................................. 175 I/M test ..................................................... 390
Identification
Engine .....................................................538
Vehicle .................................................... 537
Ignition switch (engine switch) ........207
Illuminated entry system ................... 348
Immobilizer system ................................. 79
Indicators .....................................................87
Initialization
Maintenance ........................... 385, 403
Meter .................................................. 111, 129
Moon roof ...............................................187
Multi-information display.......... 111, 129
Power windows................................... 183
Tire pressure
warning system ................................. 413
Initiators (tire pressure
warning system) .................................. 418
Inside rear view mirror......................... 176
Instrument panel light
control ............................................ 94, 100
Intercooler .............................................. 406
Intercooler coolant.............................. 404
Capacity................................................. 544
Checking ...............................................405
Preparing and checking
before winter ........................320, 320
Interior lights .......................................... 348
Intuitive parking assist ........................ 280G
H I

632 Alphabetical index
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)Tachometer ........................................ 91, 96
Variable red zone................................. 101
Tail lights................................................... 225
Light switch ........................................... 225
Replacing light bulbs ........................439
Talk switch
* Telephone switches
*Theft deterrent system
Alarm.......................................................... 80
Engine immobilizer system.............. 79
Luggage security system ................ 152
Theft prevention labels ....................... 82
Tire inflation pressure ......................... 420
Maintenance data ............................. 548
Tire inflation pressure display
function ................................................. 413
Warning light ...................................... 455
Tire information ..................................... 557
Glossary ................................................ 564
Size ........................................................... 560
Tire identification number............. 559
Uniform Tire Quality
Grading...............................................562 Tire pressure warning system ........... 413
Initializing ................................................. 413
Installing tire pressure warning
valves and transmitters.................. 413
Registering ID codes ......................... 414
Tire pressure warning reset
switch ..................................................... 414
Warning light .......................................455
Tires ............................................................. 412
Chains ..........................................322, 322
Checking ................................................. 412
Emergency tire puncture
repair kit ..............................................502
If you have a flat tire ............. 489, 502
Inflation pressure................................548
Information............................................ 557
Replacing ...............................................489
Rotating tires .......................................... 412
Size ...........................................................548
Snow tires .............................................. 323
Spare tire................................................489
Tire inflation pressure display
function.................................................. 413
Tire pressure warning system ....... 413
Warning light .......................................455T