2020 LEXUS NX300h check engine

3766-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manual_USA_M78530_en
6Turn clockwise and set the bulb
base.
7 Attach the clip to the cover.
Push up on the center of the clip and attach
the clip .
8 Attach the cover.
Align the 2 tabs positions and close the
cover and fix the cover by pushing the
center of the clip .
9Install the engine compartment
cover. ( P.347)
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WARNING
■Replacing light bulbs
●Be sure to stop the hybrid system and
turn off the lights. Do not attempt to
replace the bulb immediately after
turning off the lights.
The bulbs become very hot and may
cause burns.
●Do not touch the glass portion of the
light bulb with bare hands. When it is
unavoidable to hold the glass portion,
use and hold with a clean dry cloth to
avoid getting moisture and oils on the
bulb.
Also, if the bulb is scratched or
dropped, it may blow out or crack.
●Fully install light bulbs and any parts
used to secure them. Failure to do so
may result in heat damage, fire, or
water entering the he adlight unit. This
may damage the headlights or cause
condensation to build up on the lens.
●Do not attempt to repair or disassem-
ble light bulbs, connectors, electric cir-
cuits or component parts.
Doing so may result in death or serious
injury due to electric shock.
■To prevent damage or fire
●Make sure bulbs are fully seated and
locked.
●Check the wattage of the bulb before
installing to prevent heat damage.

3987-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78530_enpedal has been depressed and the shift
lever is in N. Release the accelerator pedal
and shift the shift lever to D, S or R.
■If “Depress Brake When Vehicle Is
Stopped Hybrid Syst
em May Overheat”
is shown
Message is displayed when the accelerator
pedal is depressed to maintain the vehicle
position when stopped on a upward slope,
etc.
If this continues, th e hybrid system may
overheat.
Release the accelerator pedal and depress
the brake pedal.
■If “Front Camera Unavailable” or “Front
Camera Unavailable See Owner’s
Manual” is displayed
The following systems may be suspended
until the problem shown in the message is
resolved. ( P.208, 389)
●PCS (Pre-Collision System)
●LTA (Lane Tracing Assist)
●LDA (Lane Departure Alert with steering
control)
●Automatic High Beam
●RSA (Road Sign Assist)
●Dynamic radar cruise control with full-
speed range
■If “RSA malfunction Visit Your Dealer” is
shown
The system may be malfunctioning. Have
the vehicle inspected by your Lexus dealer.
■If “Radar Cruise Control Unavailable
See Owner’s Manual” is shown
The dynamic radar cruise control with full-
speed range system is suspended tempo-
rarily or until the problem shown in the mes-
sage is resolved. (causes and coping
methods: P.208)
■If “Radar Cruise Control Unavailable” is
shown
The dynamic radar cruise control with full-
speed range system cannot be used tempo-
rarily. Use the system when it becomes
available again.
■If “Oil Maintenance Required Soon” is
shown
Indicates that the engine oil is scheduled to
be changed. (The indicator will not work
properly unless the oil maintenance data
has been reset.)
Check the engine oil, and change if neces-
sary. After changing th e engine oil, the oil
change system should be reset. ( P.348)
■If “Oil Maintenance Required” is shown
Indicates that the engine oil should be
changed. (After the engine oil is changed
and the oil maintenance data has been
reset.)
Check and change the en gine oil, and oil fil-
ter by your Lexus dealer. After changing the
engine oil, the oil change system should be
reset. ( P.348)
■If “See Owner’s Manual” is shown
●If the following messages are shown, fol-
lowing the instruct ions, accordingly.
• “Engine Coolant Temp High” ( P.416)
●If the following messages are shown,
there may be a malfunction.
Immediately have the vehicle inspected
by your Lexus dealer.
• “Hybrid System Malfunction”
•“Check Engine”
• “Hybrid Battery System Malfunction”
• “Accelerator System Malfunction”
• “Braking Power Low”
• “Smart Access System Malfunction”
●If “Aux Battery Low” is shown
• When the display goes off after several
seconds
*
Maintain the hybrid system operation for
more than 15 minutes and charge the 12-
volt battery.
• When the display does not go off Start up the hybrid system using the pro-
cedures for “If the 12-volt battery is dis-
charged” ( P.412).
*: Displays for about 6 seconds
●If “Maintenance required for Traction bat-
tery cooling parts” is shown, the filters
may be clogged, the air intake vents may
be blocked, or there may be a gap in the
duct. Therefore, perform the following
correction procedure.
• If the air intake vents of the hybrid battery

4177-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78530_en
7
When trouble arises
and radiator core (radiator) for any
leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4 The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Reservoir
“FULL” line
“LOW” line
5 Add coolant if necessary.
Water can be used in an emergency if coolant is unavailable.
6
Start the hybrid system and turn the
air conditioning system on to check
that the radiator cooling fans oper-
ate 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 oper-
ating by checking the fan sound and air
flow. If it is difficult to check these, turn the
air conditioning system on and off repeat-
edly.
(The fans may not oper ate in freezing tem-
peratures.)
7 If the fans are not operating:
Stop the hybrid system immediately
and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the
nearest Lexus dealer.
8 Check if “Engine Coolant Temp
High” is shown on the multi-infor-
mation display.
If the message does not disappear:
Stop the hybrid system and contact
your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the
nearest Lexus dealer.
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4187-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78530_en
■If “Hybrid System Overheated” is
shown on the multi-information dis-
play
1 Stop the vehicle in a safe place.
2 Stop the hybrid system and care-
fully lift the hood.
3 After the hybrid system has cooled
down, inspect the hoses and radia-
tor core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immedi-
ately contact your Lexus dealer.
4The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Reservoir “FULL” line
“LOW” line 5
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
6After stopping the hybrid system
and waiting for 5 minutes or more,
start the hybrid system again and
check if “Hybrid System Over-
heated” is shown on the multi-infor-
mation display.
If the message does not disappear:
Stop the hybrid system and contact your
Lexus dealer.
If the message is not displayed:
The hybrid system temperature has
dropped and the vehicle may be driven
normally.
However, if the message appears again fre-
quently, contact your Lexus dealer.
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WARNING
■To prevent an accident or injury when
inspecting under the hood of your
vehicle
Observe the following precautions.
Failure to do so may result in serious
injury such as burns.
●If steam is seen coming from under the
hood, do not open the hood until the
steam has subsided. The engine com-
partment may be very hot.

4197-2. Steps to take in an emergency
LEXUS NX300h Owners Manual_USA_M78530_en
7
When trouble arises
1 Stop the hybrid system. Shift the
shift lever to P and set the parking
brake.
2 Remove the mud, snow or sand
from around the front wheels.
3 Place wood, stones or some other
material under the front wheels to
help provide traction.
4 Restart the hybrid system.
5 Shift the shift lever to D or R,
release the parking brake. Then,
while exercising caution, depress
the accelerator pedal.
■When it is difficult to free the vehicle
Press to turn off TRAC. ( P.271)
WARNING
●After the hybrid system has been
turned off, check that the “READY”
indicator is off. When the hybrid sys-
tem is operating, the gasoline engine
may automatically start, or the cooling
fan may suddenly operate even if the
gasoline engine stops. Do not touch or
approach rotating parts such as the
fan, which may lead to fingers or cloth-
ing (especially a tie, a scarf or a muf-
fler) getting caught, resulting in serious
injury.
●Do not loosen the coolant reservoir
cap while the hybrid system and radia-
tor are hot.
High temperature steam or coolant
could spray out.
NOTICE
■When adding engine/power control
unit coolant
Add coolant slowly after the hybrid sys-
tem has cooled down sufficiently. Adding
cool coolant to a hot hybrid system too
quickly can cause damage to the hybrid
system.
■To prevent damage to the cooling sys-
tem
Observe the following precautions:
●Avoid contaminating the coolant with
foreign matter (such as sand or dust
etc.).
●Do not use any coolant additive.
If the vehicle becomes stuck
Carry out the following proce-
dures if the tires spin or the vehicle
becomes stuck in mud, dirt or snow:
Recovering procedure

4248-1. Specifications
LEXUS NX300h Owners Manual_USA_M78530_en
Rear
■Oil capacity (Drain and refill [Reference*])
*: The engine oil capacity is a reference quantity to be used when changing the engine oil. Warm up the engine and turn off the hybrid system, wait more than 5 minutes, and check
the oil level on the dipstick.
■Engine oil selection
“Toyota Genuine Motor Oil” is used in
your Lexus vehicle. Use Lexus
approved “Toyota Genuine Motor Oil”
or equivalent to satisfy the following
grade and viscosity.
Oil grade: ILSAC GF-5 multigrade
engine oil
Recommended viscosity: SAE 0W-20
SAE 0W-20 is the best choice for
good fuel economy and good starting
in cold weather.
If SAE 0W-20 is not available, SAE 5W-20 oil may be used. However, it
must be replaced with SAE 0W-20 at
the next oil change.
Outside temperature
Oil viscosity (0W-20 is explained here
TypePermanent magnet synchronous motor
Maximum output50 kW
Maximum torque103 ft•lbf (139 N•m, 14.2 kgf•m)
Hybrid battery (traction battery)
TypeNickel-Metal hydride battery
Voltage7.2 V/module
Capacity6.5 Ah (3HR)
Quantity34 modules
Nominal voltage244.8 V
Lubrication system
With filter4.6 qt. (4.4 L, 3.9 Imp.qt.)
Without filter4.2 qt. (4.0 L, 3.5 Imp.qt.)
A

LEXUS NX300h Owners Manual_USA_M78530_en
Alphabetical Index473
Emergency flashers .................................... 378
Emergency, in case ofIf a warning buzzer sounds ..................386
If a warning light turns on ......................386
If a warning message is displayed.....396
If the 12-volt battery is discharged ...... 412
If the electronic key does not operate properly........................................................ 410
If the fuel filler door cannot be opened .........................................................................409
If the hybrid system will not start ........ 407
If the vehicle is trapped in rising water ......................................................................... 379
If you have a flat tire ................................. 400
If you lose your keys.................................409
If you think something is wrong .........384
If your vehicle becomes stuck...............419
If your vehicle has to be stopped in an
emergency ................................................ 378
If your vehicle needs to be towed ...... 381
If your vehicle overheats ..........................416
Energy monitor ............................................... 99
Engine Accessory mode ......................................... 176
Compartment ............................................. 346
Engine switch................................................. 174
Hood................................................................ 344
How to start the hybrid system ............ 174
Identification number ............................... 423
If your vehicle has to be stopped in an
emergency ................................................ 378
Ignition switch (power switch) .............. 174
Overheating...................................................416
Power switch ................................................. 174 Engine compartment cover .................... 347
Engine coolant
Capacity .........................................................425
Checking .......................................................349
Preparing and checking before winter.......................................................................... 277
Warning light ...............................................387
Engine coolant temperature gauge ....... 84
Engine oil Capacity ......................................................... 424
Checking ....................................................... 347
Warning light ...............................................387
Engine switch .................................................. 174
EPS (Electronic Power Steering) Function .......................................................... 270
Warning light .............................................. 388
EV drive mode................................................ 177
EV indicator ...................................................... 68
Event data recorder (E DR) ........................... 8
F
Flat tire .............................................................400
Tire pressure warning system .............357
Floor mats .......................................................... 24
Fluid Brake ................................................................ 427
Transmission................................................. 426
Washer ............................................................ 351
Fog lights Replacing light bulbs ................................ 374
Switch................................................................ 195
Front passenger occupant classification system ................................................................ 41

482Alphabetical Index
LEXUS NX300h Owners Manual_USA_M78530_en
W
Warning buzzers Approach warning.................................... 242
Downshifting ..................................................182
Intuitive parking assist................................251
Light reminder.............................................. 190
Open door......................................................... 111
Seat belt reminder.......................................391
Vehicle sway warning ................... 221, 230
Warning lights ABS ................................................................. 388
Brake hold operated indicator ...........390
Brake Override System ......................... 393
Brake system ...............................................386
Charging system .......................................386
Drive-Start Control .................................. 393
Electric power steering ......................... 388
High coolant temperature .................... 387
LDA indicator..............................................389
Low engine oil pressure......................... 387
Low fuel level .................................................391
LTA indicator ...............................................389
Malfunction indicator lamp................... 387
Master warning light ................................ 392
Parking brake indicator ..........................390
PCS warning light .....................................389
PKSB OFF indicator ................................390
Seat belt reminder light ............................391
Slip indicator ................................................390
SRS................................................................... 388
Tire pressure ................................................ 392
Warning messages ..................................... 396 Washer
Checking ........................................................ 351
Low washer fluid warning message 351, 396
Preparing and checking before winter .......................................................................... 277
Switch....................................................195, 200
Washing and waxing.................................. 330
Weights Cargo capacity ........................ 161, 164, 422
Load limits ..................................................... 422
Weights .......................................................... 422
Wheels ............................................................. 365 Replacing wheels ...................................... 365
Size ....................................................................428
Window glasses ............................................ 148
Window lock switch .....................................149
Windows Power windows ........................................... 148
Rear window defogger.......................... 290
Washer ................................................195, 200
Windshield wiper de-icer ........................ 294
Windshield wipers Intermittent windshield wipers ............. 195
Rain-sensing windshield wipers ...........197
Winter driving tips........................................277
Wireless charger ...........................................312
Wireless remote control key ....................107 Battery-saving function............................. 127
Locking/Unlocking ................................... 107
Panic mode ....................................................108
Replacing the battery .............................. 368