ECU LEXUS RC300 2018 Repair Manual

446 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)If your vehicle is transported by a flat-
bed truck, it should be tied down at the
locations shown in the illustration.
If you use chains or cables to tie down
your vehicle, the angles shaded in black
must be 45  .
Do not overly tighten the tie downs or
the vehicle may be damaged.
If a tow truck is not available in an em ergency, your vehicle may be temporarily
towed using cables or chains secured to the emergency towing eyelets. This
should only be attempted on hard surf aced roads for at most 50 miles (80 km)
at under 18 mph (30 km/h).
A driver must be in the vehicle to st eer and operate the brakes. The vehicle’s
wheels, drive train, axles, steering an d brakes must be in good condition.Using a flatbed truck
Emergency towing

448 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)Insert the towing eyelet into the hole
and tighten partially by hand.
Tighten down the towing eyelet
securely using a wheel nut wrench
or hard metal bar.
Securely attach cables or chains to the towing eyelet. Take care not to damage the vehicle body.
Enter the vehicle being towed and start the engine. If the engine does not start, turn the engine switch to IGNITION ON mode.
Shift the shift lever to N and release the parking brake.
When the shift lever cannot be shifted:  P. 219■
While towing
If the engine is not running, the power assist for the brakes and steering will not function,
making steering and br aking more difficult.■
Wheel nut wrench
Wheel nut wrench is installed in trunk. (  P. 490, 504)3
4
5
6
7

450 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)WARNING ■
While towing ●
When towing using cables or chains, avoid sudden starts, etc. which place excessive
stress on the towing eyelets, cables or chains. The towing eyelets, cables or chains
may become damaged, broken debris ma y hit people, and cause serious damage.●
Do not turn the engine switch off.
There is a possibility that the steering wheel is locked and cannot be operated.■
Installing towing eyelets to the vehicle
Make sure that towing eyel ets are installed securely.
If not securely installed, towing ey elets may come loose during towing.
NOTICE ■
To prevent damage to the vehicle when towing using a wheel-lift type truck●
Do not tow the vehicle from the rear when the engine switch is off. The steering lock
mechanism is not strong enough to hold the front wheels straight. ●
When raising the vehicle, en sure adequate ground cleara nce for towing at the oppo-
site end of the raised vehicle. Without ad equate clearance, the vehicle could be dam-
aged while being towed. ■
To prevent damage to the vehicle wh en towing with a sling-type truck
Do not tow with a sling-type truck, either from the front or rear. ■
To prevent damage to the ve hicle during emergency towing
Do not secure cables or chains to the suspension components.

4577-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U) 7
When trouble arises ■
SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors, side
impact sensors (door), side impact sensors (front), side im pact sensors (rear), driver’s
seat position sensor, driver’s seat belt buckle switch, front passenger occupant classifica-
tion system, “AIR BAG ON” indicator light, “A IR BAG OFF” indicator light, front passen-
ger’s seat belt buckle switch, seat belt pretensioners, airbags, interconnecting wiring and
power sources. (  P. 41) ■
Front passenger detection sensor, seat belt reminder and warning buzzer
If luggage is placed on the front passenger seat, the front passenger detection sensor
may cause the warning light to flash and the warning buzzer to sound even if a passenger
is not sitting in the seat. ■
If the malfunction indicator lamp comes on while driving
First check the following: ●
Is the fuel tank empty?
If it is, fill the fu el tank immediately.●
Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving trips.
If the light does not go off even after severa l trips, contact your Lexus dealer as soon as
possible. ■
Electric power steering system warning light (warning buzzer)
When the battery charge becomes insufficien t or the voltage temporarily drops, the
electric power steering system warning li ght may come on and the warning buzzer may
sound. ■
When the tire pressure warning light comes on
Check the tire inflation pressu re and adjust to the approp riate level. Pushing the tire
pressure warning reset switch will not tu rn off the tire pressure warning light.■
The tire pressure warning light ma y come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air
leaks and tire inflation pressure changes caus ed by temperature. In this case, adjusting
the tire inflation pressure will turn off the warning light (aft er a few minutes).■
When a tire is replaced with the spare tire (if equipped)
The spare tire is not equipped with a tire pr essure warning valve and transmitter. If a tire
goes flat, the tire pressure warning light will not turn off even though the flat tire has been
replaced with the spare tire. ■
Conditions that the tire pressure wa rning system may not function properly
 P. 417 ■
If the tire pressure warning light freque ntly comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when the
engine switch is turned to IGNITION ON mo de, have it checked by your Lexus dealer.■
Warning buzzer
In some cases, the buzzer ma y not be heard due to being in a noisy location or audio
sound.

486 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)Once  • When the doors were unlocked
with the mechanical key and then
the engine swit ch was pressed,
the electronic key could not be
detected in the vehicle.
• The electronic key could not be
detected in the vehicle even after
the engine switch was pressed
two consecutive times.
 Touch the electronic key to the
engine switch while depressing
the brake pedal.
Once  During an engine starting proce-
dure in the event that the electronic
key was not functioning properly
(  P. 520), the engine switch was
touched with the electronic key.
 Press the engine switch within
10 seconds of the buzzer sound-
ing.
  Indicates that:
• With the engine switch off, the
doors were unlocked and then the
driver's door was opened and
closed.
• The engine switch was turned to
ACCESSORY mode without
starting the engine.
• The shift lever wa s shifted to P or
N from another shift position with
the engine switch in IGNITION
ON mode.
 Press the engine switch while
depressing the brake pedal.Interior
buzzer Exterior
buzzer Warning message Details/Actions

494 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)
RC350/RC300
Hold the hook and lift up the lug-
gage mat.
Secure the luggage mat using the
hook.
Remove the tool tray.
Take out the jack.
For tightening
For loosening If the jack is too tightly installed to be
removed by hand, insert a tool, such
as the screwdriver included with the
vehicle, into the hole of the jack (por-
tion “A”) and loosen the jack.Taking out the jack 1
2
3
4
1
2

496 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)
RC350/RC300
Secure the luggage mat using the hook. (  P. 494)
Remove the tool tray.
Loosen the center fastener that
secures the spare tire. If the center fastener cannot be turned
by hand, use the wheel nut wrench that
is stored in the trunk. (To secure the tire,
tighten the center fastener by hand. Do
not use the wrench or other tools.) 
RC F
Remove the luggage mat.
Loosen the center fastener that
secures the spare tire. If the center fastener cannot be turned
by hand, use the wheel nut wrench that
is stored in the trunk. (To secure the tire,
tighten the center fastener by hand. Do
not use the wrench or other tools.)Taking out the spare tire 1
2
3
1
2

5017-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U) 7
When trouble arises WARNING ■
When using the spare tire ●
Remember that the spare tire provided is specifically designed for use with your vehi-
cle. Do not use your spare tire on another vehicle. ●
Do not use more than one spare tires simultaneously. ●
Replace the spare tire with a stan dard tire as soon as possible.●
Avoid sudden acceleration, abrupt steering, sudden braking and shifting operations
that cause sudden engine braking. ■
When the spare tire is attached
The vehicle speed may not be correctly detected, and the following systems may not
operate correctly:
Also, not only can the following system not be utilized fully, but it may even negatively
affect the drive-train components:
• AWD system (if equipped) ■
Speed limit when using the spare tire
Do not drive at speeds in excess of 50 mp h (80 km/h) when a spar e tire is installed on
the vehicle.
The spare tire is not designed for driving at high speeds. Fa ilure to observe this precau-
tion may lead to an accident causing death or serious injury. ■
After using the tools and jack
Before driving, make sure all the tools and jack are securely in place in their storage
location to reduce the possibilit y of personal injury during a collision or sudden brak-
ing.
NOTICE ■
Driving with tire chains and the spare tire
Do not fit tire chains to the spare tire.
Tire chains may damage the vehicle body and adversely affect driving performance.■
When replacing the tires
When removing or fitting the wheels, tires or the tire pressure warning valve and trans-
mitter, contact your Lexus dealer as the tire pressure warning valve and transmitter
may be damaged if not handled correctly.• ABS & Brake assist
•VSC
•TRAC
• Dynamic radar cruise control
•PCS
•EPS
• Adaptive Variable Suspension System
(if equipped)
• LDA (Lane Departure Alert with
steering control)
• VGRS (if equipped) • LDH (Lexus Dynamic Handling sys-
tem) (if equipped)
• DRS (Dynamic Rear Steering) (if
equipped)
• VDIM (Vehicle Dynamics Integrated
Management)
• Tire pressure warning system
• Lexus parking assist monitor
• Intuitive parking assist (if equipped)
• Navigation system (if equipped)

506 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)Secure the luggage mat using the hook. (  P. 494)
Remove the tool tray.
Take out the emergency tire
puncture repair kits.Taking out the emergency tire puncture repair kits 1
2
3

508 7-2. Steps to take in an emergency
RC350_RC300 AWD_RC3 00_RC F_U(OM24748U)Lift the rubber stopper on the com-
pressor.
Remove the power plug from the
compressor.
Connect the power plug to the power outlet socket. (  P. 355)
Connect the bottle to the compres-
sor. Make sure that the bottle is securely
connected. 5
6
7
8