Page 505 of 680

5057-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_OM_USA_OM78082U
■Adding engine oil
If the oil level is below or near the
low level mark, add engine oil of the
same type as that already in the
engine.
Make sure to check the oil type and prepare the items needed before adding
oil.Remove the oil filler cap by turning it counterclockwise.
Add engine oil slowly, checking the dipstick.
Install the oil filler cap by turning it clockwise.
■Engine oil consumption
A certain amount of engine oil will be consum ed while driving. In the following situations,
oil consumption may increase, and engine o il may need to be refilled in between oil
maintenance intervals.
●When the engine is new, for example directly after purchasing the vehicle or after
replacing the engine
●If low quality oil or oil of an inappropriate viscosity is used
●When driving at high engine speeds or with a heavy load, when towing, or when driving
while accelerating or decelerating frequently
●When leaving the engine idling for a long time, or when driving frequently through
heavy traffic
Engine oil selection P. 6 1 0
Oil quantity (Low Full)1.6 qt. (1.5 L, 1.3 Imp.qt.)
ItemsClean funnel
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Page 507 of 680

5077-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_OM_USA_OM78082U
WA R N I N G
■Used engine oil
●Used engine oil contains potentially harmful contaminants which may cause skin dis-
orders such as inflammation and skin canc er, so care should be taken to avoid pro-
longed and repeated contact. To remove used engine oil from your skin, wash
thoroughly with soap and water.
●Dispose of used oil and filters only in a sa fe and acceptable manner. Do not dispose of
used oil and filters in household trash, in sewers or onto the ground. Call your Lexus
dealer, service station or auto parts store for information concerning recycling or dis-
posal.
●Do not leave used engine oil within the reach of children.
NOTICE
■To prevent serious engine damage
Check the oil level on a regular basis.
■When replacing the engine oil
●Be careful not to spill engine oil on the vehicle components.
●Avoid overfilling, or the engine could be damaged.
●Check the oil level on the dipstick every time you refill the vehicle.
●Be sure the engine oil filler cap is properly tightened.
Page 508 of 680

5087-3. Do-it-yourself maintenance
NX300h_OM_USA_OM78082U
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir when the hybrid system is cold.
■Engine coolant reservoir Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( P. 599)
■Power control unit coolant reservoir
Reservoir 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 mixt ure of 50% coolant and 50% deionized water.
(Minimum temperature: -31 F [-35 C])
Canada:
“Toyota Super Long Life Coolant” is a mixt ure 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/p ower 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.
Coolant
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Page 509 of 680

5097-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_OM_USA_OM78082U
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.
Page 534 of 680
5347-3. Do-it-yourself maintenance
NX300h_OM_USA_OM78082U
Checking and replacing fuses
Turn the power switch off.
Open the fuse box cover.
If any of the electrical components do not operate, a fuse may have blown. If
this happens, check and replace the fuses as necessary.
1
2
Engine compartment: type A fuse
box Engine compartment: type B fuse
box
Push the tab in and lift the lid off. Push the tab in and lift the lid off.
Left side instrument panel
Remove the lid.
Page 538 of 680
5387-3. Do-it-yourself maintenance
NX300h_OM_USA_OM78082U
Light bulbs
Check the wattage of the light bulb to be replaced. ( P. 6 1 5 )
P. 5 0 3
P. 1 3 2
You may replace the following bulbs by yourself. The difficulty level of replace-
ment varies depending on the bulb. If necessary bulb replacement seems diffi-
cult to perform, contact your Lexus dealer.
For more information about replacing other light bulbs, contact your Lexus
dealer.
Preparing for light bulb replacement
Removing the engine compartment cover
Canceling the power back door system
Page 574 of 680

5748-2. Steps to take in an emergency
NX300h_OM_USA_OM78082U
■If “Depress Brake When Vehicle Is Stopped Hybrid System 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, the hybrid system may overheat.
Release the accelerator pedal and depress the brake pedal.
■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 necessary. After changing the engine oil, the oil
change system should be reset. ( P. 5 0 6 )
■If “Oil Maintenance Required” is shown
Indicates that the engine oil should be change d. (After the engine oil is changed and the
oil maintenance data has been reset.)
Check and change the engine oil, and oil filter by your Lexus dealer. After changing the
engine oil, the oil change system should be reset. ( P. 5 0 6 )
■If “See Owner’s Manual” is shown
●If the following messages are shown, following the instructions, accordingly.
• “Engine Coolant Temp High” ( P. 5 9 9 )
●If the following messages are sh own, 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 the following messages are sh own, there may be a malfunction.
Immediately stop the vehicle in a safe place and contact your Lexus dealer. Continuing
to drive the vehicle may be dangerous.
•“Low Oil Pressure”
• “Charging System Malfunction”
■Warning buzzer
P. 5 6 9
NOTICE
■“High Power Consumption Partial Limit On AC/Heater Operation” is frequently
shown
There is a possible malfunction relating to the charging system or the 12-volt battery
may be deteriorating. Have the vehicle inspected by your Lexus dealer.
Page 600 of 680

6008-2. Steps to take in an emergency
NX300h_OM_USA_OM78082U
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.
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