3326-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
al_USA_M78287_en
■Power control unit coolant reser-
voirReservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW” line,
add coolant up to the “FULL” line.
■Coolant selection
Only use “Toyota Super Long Life Coolant”
or a similar high quality ethylene glycol
based non-silicate, non-amine, non-nitrite,
and non-borate coolant with long-life
hybrid organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mix-
ture of 50% coolant and 50% deionized
water.
(Minimum temperature: -31°F [-35°C])
Canada:
“Toyota Super Long Life Coolant” is a mix-
ture of 55% coolant and 45% deionized
water.
(Minimum temperature: -44°F [-42°C])
For more details about coolant, contact
your Lexus dealer.
■If the coolant level drops within a short
time of replenishing
Visually check the radiator, hoses, engine/
power control unit coolant reservoir caps,
drain cock and water pump.
If you cannot find a leak, have your Lexus
dealer test the cap and check for leaks in
the cooling system.
Check the radiator and condenser and
clear away any foreign objects.
If either of the above parts is extremely
dirty or you are not sure of their condi-
tion, have your vehicle inspected by
your Lexus dealer.
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WARNING
■When the hybrid system is hot
Do not remove the en gine/power control
unit coolant reservoir caps.
The cooling system may be under pres-
sure and may spray hot coolant if the cap
is removed, causing serious injuries, such
as burns.
NOTICE
■When adding coolant
Coolant is neithe r plain water nor
straight antifreeze. The correct mixture
of water and antifreeze must be used to
provide proper lubrication, corrosion
protection and cooling. Be sure to read
the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to pre-
vent it from damaging parts or paint.
Checking the radiator and con-
denser
WARNING
■When the hybrid system is hot
Do not touch the radiator or condenser
as they may be hot and cause serious
injuries, such as burns.
3336-3. Do-it-yourself maintenance
LEXUS NX300h Owners Manu-
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6
Maintenance and care
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN” lines
on the tank.
■Adding fluid
Make sure to check the fluid type and
prepare the necessary item.
Fluid type
FMVSS No.116 DOT 3 or SAE J1703;
FMVSS No.116 DOT 4 or SAE J1704
brake fluid
Items
Clean funnel
■Brake fluid can absorb moisture from
the air
Excess moisture in the brake fluid can cause a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
If none of the washer do not work or
the “Windshield Washer Fluid Low” on
the multi-information display, the
washer tank may be empty. Add
washer fluid.
WARNING
■When the electric cooling fans are
operating
Do not touch the engine compartment.
With the power switch in ON mode, the
electric cooling fans may automatically
start to run if the air conditioning is on
and/or the coolant temperature is high.
Be sure the power switch is off when
working near the electric cooling fans or
radiator grille.
Checking and adding the brake
fluid
WARNING
■When filling the reservoir
Take care as brake fluid can harm your
hands and eyes and damage painted sur-
faces.
If fluid gets on your hands or in your eyes,
flush the affected area with clean water
immediately.
If you still experience discomfort, see a
doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go
down slightly as the brake pads wear out
or when the fluid leve l in the accumulator
is high.
If the reservoir need s frequent refilling,
there may be a serious problem.
Checking and adding the washer
fluid
3967-2. Steps to take in an emergency
LEXUS NX300h Owners Manu-
al_USA_M78287_en
“Engine Coolant Temp High” is
shown on the multi-information dis-
play
1 Stop the vehicle in a safe place and
turn off the air conditioning system,
and then stop the hybrid system.
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 hybrid system has cooled
down sufficiently, inspect the hoses 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
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
The needle of the engine coolant
temperature gauge ( P.79)
enters the red zone, or a loss of
hybrid system power is experi-
enced. (For example, the vehicle
speed does not increase.)
“Engine Coolant Temp High” or
“Hybrid System Overheated” is
shown on the multi-information
display.
Steam comes out from under the
hood.
Correction procedures
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3977-2. Steps to take in an emergency
LEXUS NX300h Owners Manu-
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7
When trouble arises
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.
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 (radiato r) 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.
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458Alphabetical Index
LEXUS NX300h Owners Manu-
al_USA_M78287_en
TRAC (Traction Control) ........................ 250
Traction battery (Hybrid battery) ............ 64 Hybrid battery (traction battery) air intake and discharge vents................... 66
Location............................................................. 64
Specification .................................................403
Warning messages ..................................... 67
Traction motor (electric motor) ................. 61
Trailer Sway Control.................................. 250
Trailer towing ........................................ 159, 167
Transmission Hybrid transmission ................................... 173
Selecting a driving mode....................... 248
Trip meters .........................................................79
Turn signal lights Replacing light bulbs................... 355, 356
Turn signal lever ........................................... 176
Wattage..........................................................409
V
Vanity lightsVanity lights ..................................................286
Wattage..........................................................409
Vanity mirrors ............................................... 286 Vanity lights ..................................................286
Vehicle data recordings ..................................7
Vehicle identification number ................ 402
Vehicle Stability Control (VSC) ........... 249
VSC (Vehicle Stabilit y Control) ........... 249
W
Warning buzzers
Approach warning.................................... 222
Downshifting ..................................................176
Intuitive parking assist ................................231
Light reminder .............................................. 183
Open door ..................................................... 105
Seat belt reminder .......................................371
Vehicle sway warning .............................. 210
Warning lights ABS .................................................................. 369
Brake hold operated indicator ...........370
Brake Override System ......................... 373
Brake system................................................ 367
Charging system........................................ 367
Drive-Start Control................................... 373
Electric power steering.......................... 369
High coolant temperature.................... 368
LDA indicator ..............................................370
Low engine oil pressure........................ 368
Low fuel level .................................................371
Malfunction indicator lamp .................. 368
Master warning light................................. 372
Parking brake indicator ............................371
PCS warning light .................................... 369
PKSB OFF indicator ................................370
Seat belt reminder light.............................371
Slip indicator .................................................370
SRS ................................................................... 369
Tire pressure ................................................ 372