2015 LEXUS NX300h radiator

5097-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_U_OM78007U 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. WA R N I N G ■
When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps.
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing serious injuries, such as burns.
NOTICE ■
When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of water and
antifreeze must be used to provide proper lubrication, corrosion protection and cool-
ing. Be sure to read the antifreeze or coolant label. ■
If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.
Radiator and condenser WA R N I N G ■
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. ■
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.

600 8-2. Steps to take in an emergency
NX300h_U_OM78007UIf your vehicle overheats ■
“Engine Coolant Temp High” is shown on the multi-information display
Stop the vehicle in a safe place and tu rn off the air conditioning system, and
then stop the hybrid system.
If you see steam: Carefully lift the hood after the steam subsides.
If you do not see steam: Carefully lift the hood.
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,
immediately contact your Lexus
dealer.The following may indicate that your vehicle is overheating. ●
The needle of the engine coolant temperature gauge (  P. 97) enters the
red zone, or a loss of hybrid system po wer is experienced. (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 1
2
3
1
2

6018-2. Steps to take in an emergency
8
When trouble arises
NX300h_U_OM78007U The coolant level is satisfactory if it is between the “FULL” and “LOW” lines
on the reservoir.
Reservoir
“FULL” line
“LOW” line
Add coolant if necessary. Water can be used in an emergency
if coolant is unavailable.
Start the hybrid system and turn the air conditioning system on to check
that the radiator 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 op erating by checking the fan sound and air
flow. If it is difficult to check these, tu rn the air conditioning system on and off
repeatedly. (The fans may not operate in freezing temperatures.)
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.
Check if “Engine Coolant Temp High” is shown on the multi-information
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. 4
1
2
3
5
6
7
8

602 8-2. Steps to take in an emergency
NX300h_U_OM78007U ■
If “Hybrid System Overheated” is shown on the multi-information display
Stop the vehicle in a safe place.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has cooled down, inspect the hoses and radiator
core (radiator) for any leaks.
Radiator
Cooling fans If a large amount of coolant leaks,
immediately contact your Lexus
dealer.
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines
on the reservoir.
Reservoir
“FULL” line
“LOW” line
Add coolant if necessary. Water can be used in an emergency
if coolant is unavailable. 1
2
3
1
2
4
1
2
3
5

6038-2. Steps to take in an emergency
8
When trouble arises
NX300h_U_OM78007U Start the hybrid system and check if “Hybrid System Overheated” is shown
on the multi-information 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. WA R N I N G ■
To prevent an accident or injury when in specting 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 h ood, do not open the hood until the steam
has subsided. The engine compartment may be very hot. ●
After the hybrid system has been turned off, check that the “READY” indicator are
off.
When the hybrid system is operating, the gasoline engine may au tomatically start, or
the cooling fan may suddenly operate even if the gasoline engine stops. Do not touch
or approach rotating parts such as the fa n, which may lead to fingers or clothing
(especially a tie, a scarf or a muffler) ge tting caught, resulting in serious injury.●
Do not loosen the coolant reservoir cap while the hybrid system and radiator are hot.
High temperature steam or coolant could spray out.
NOTICE ■
When adding engine/power control unit coolant
Add coolant slowly after the hybrid system 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 system
Observe the following precautions: ●
Avoid contaminating the coolant with foreign matter (such as sand or dust etc.). ●
Do not use any coolant additive. 6

672 Alphabetical index
NX300h_U_OM78007U Multi-information display
Drive information ................................ 103
Dynamic radar cruise
control ..................................................240
Dynamic radar cruise control
with full-speed range ....................253
Energy monitor ........................................ 111
Language .............................................. 638
LDA (Lane Departure Alert
with steering control) ...................253
Warning messages........................... 572
Navigation system
*Noise from under vehicle ....................... 8
Odometer ...................................................97
Oil
Engine oil................................................... 611
Rear differential oil .............................. 614
Opener
Back door ............................................... 130
Fuel filler door ......................................236
Hood ....................................................... 500
Outside rear view mirrors ..................163
Adjusting and folding........................ 163
Blind Spot Monitor (BSM)............. 316
Linked mirror function
when reversing ................................. 164
Mirror position memory .................. 154
Outside rear view mirror
defoggers ...........................................435 Outside temperature display .............. 97
Overheating........................................... 600
Panic mode ................................................ 119
Parking brake
Operation................................................ 213
Parking brake engaged
warning buzzer/message ........... 215
Warning light .......................................566
Parking lights
Light switch............................................. 219
Replacing light bulbs ....................... 552
Warning light .......................................566
PCS (Pre-Collision System)
Function ................................................... 310
PCS switch ...............................................311
Warning light .......................................566
Warning message............................. 572
Personal lights ........................................443
Switch ...................................................... 444
Power back door opener and
closer ....................................................... 129
Power control unit coolant
Capacity...................................................613
Checking .............................................. 508
Preparing and checking
before winter .................................... 326
Radiator ................................................. 509N
O P

673Alphabetical index
NX300h_U_OM78007U Power easy access system .................154
Power outlets ......................................... 456
Power steering (Electric Power
Steering system) ................................305
Warning light ...................................... 566
Power switch ........................................... 201
Power windows
Door lock linked window
operation ..............................................167
Jam protection function ....................167
Operation ............................................... 166
Window lock switch.......................... 166
Pre-Collision System (PCS)
Function ................................................... 310
PCS switch............................................... 311
Warning light ...................................... 566
Warning message ............................. 572
Radar cruise control (dynamic
radar cruise control) ........................ 240
Radar cruise control
(dynamic radar cruise control
with full-speed range) ..................... 253
Radiator ....................................................509
Radio............................................................361
Rear Cross Traffic Alert ......................316
Rear seat
Folding down the rear
seatbacks ............................................. 148 Rear side marker lights
Light switch............................................. 219
Replacing light bulbs ....................... 552
Rear turn signal lights
Replacing light bulbs ....................... 547
Turn signal lever ................................... 212
Wattage ................................................... 617
Rear view mirror
Inside rear view mirror....................... 161
Outside rear view mirrors ..............163
Rear window defogger ...................... 435
Rear window wiper ..............................234
Refueling...................................................236
Capacity.................................................. 610
Fuel types................................................ 610
Opening the fuel tank cap ............ 236
When the fuel filler door
cannot be opened ......................... 238
Regenerative braking............................. 79
Remote Touch
* Replacing
Electronic key battery ..................... 532
Fuses ........................................................ 534
Light bulbs.............................................538
Tires .......................................................... 575
Resetting the message indicating
maintenance is required .................492
Reporting safety defects
for U.S. owners ...................................646
Road accident cautions ........................ 84R
* : Refer to the “NAVIGATION SYSTEM OWNER’S MANUAL”.