engine LEXUS NX300h 2015 Repair Manual

564 8-2. Steps to take in an emergency
NX300h_U_OM78007UIf you think something is wrong ●
Fluid leaks under the vehicle
(Water dripping from the air co nditioning after use is normal.)●
Flat-looking tires or uneven tire wear ●
Engine coolant temperature gauge needle continually points higher than nor-
mal ●
Changes in exhaust sound ●
Excessive tire squeal when cornering ●
Strange noises related to the suspension system ●
Pinging or other noises related to the hybrid system ●
Engine misfire or misses, st umbling or running roughly●
Appreciable loss of power ●
Vehicle pulls heavily to one side when braking ●
Vehicle pulls heavily to one side when driving on a level road ●
Loss of brake effectiveness, spongy f eeling, pedal almost touches the floorIf you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

565
8
When trouble arises 8-2. Steps to take in an emergency
NX300h_U_OM78007UIf a warning light turns on or a warning buzzer
sounds Calmly perform the following actions if any of the warning lights comes on or
flashes. If a light comes on or flashes, bu t then goes off, this does not necessar-
ily indicate a malfunction in the system. However, if this continues to occur,
have the vehicle inspected by your Lexus dealer.
Warning light and warning buzzer list Warning light Warning light/Details/Actions(U.S.A.)
(Canada)
Brake system warning light
Indicates that:
• The brake fluid level is low; or
• The brake system is malfunctioning
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
* 1
Charging system warning light
Indicates a malfunction in the vehicle’s charging system
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
* 1
Low engine oil pressure warning light (warning buzzer)
Indicates that the engine oil pressure is too low
 Immediately stop the vehicle in a safe place and contact your
Lexus dealer. Continuing to drive the vehicle may be dangerous.
* 1
High coolant temperature warning light (warning buzzer)
Indicates that the engine is overheating
 Immediately stop the vehicle in a safe place. Continuing to drive
the vehicle may be dangerous.
Handling method (  P. 600)
Brake system warning light
Indicates a malfunction in:
• The regenerative braking system;
• The electronically controlled brake system; or
• The electric parking brake
 Have the vehicle inspected by your Lexus dealer immediately. (U.S.A.)
(Canada)
Malfunction indicator lamp
Indicates a malfunction in:
• The hybrid system;
• The electronic engine control system;
• The electronic throttle control system; or
• The emission control system
 Have the vehicle inspected by your Lexus dealer immediately.

574 8-2. Steps to take in an emergency
NX300h_U_OM78007U ■
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 necessar y. 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 changed. (After the engine oil is changed and the
oil maintenance data has been reset.)
Check and change the engine oil, and oil filt er 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 instru ctions, accordingly.
• “Engine Coolant Temp High” (  P. 6 0 0 )●
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.

595
8
When trouble arises 8-2. Steps to take in an emergency
NX300h_U_OM78007UIf the 12-volt battery is discharged If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt
battery, you can jump start your vehicle by following the steps below.
Open the hood (  P. 5 0 0 ) a n d f u s e
box cover.
Open the exclusive jump starting
terminal cover.
Remove the engine cover.The following procedures may be used to start the hybrid system if the vehi-
cle’s 12-volt battery is discharged.
You can also call your Lexus dealer or a qualified repair shop. 1
2
3

5978-2. Steps to take in an emergency
8
When trouble arises
NX300h_U_OM78007U Start the engine of the second vehicle. Increase the engine speed slightly and
maintain at that level for approximately 5 minutes to recharge the 12-volt bat-
tery of your vehicle.
Open and close any of the doors of your vehicle with the power switch off.
Maintain the engine speed of the second vehicle and start the hybrid system
of your vehicle by turning the power switch to ON mode.
Make sure the “READY” indicator comes on. If the indicator light does not
come on, contact your Lexus dealer.
Once the hybrid system has started, remove the jumper cables in the exact
reverse order from which they were connected.
Close the exclusive jump starting terminal cover, and reinstall the fuse box
cover to its original position.
Once the hybrid system starts, have th e vehicle inspected at your Lexus dealer
as soon as possible. ■
Starting the hybrid system when the 12-volt battery is discharged
The hybrid system cannot be started by push-starting. ■
To prevent 12-volt battery discharge ●
Turn off the headlights and the audio system while the hybrid system is off. ●
Turn off any unnecessary electrical components when the vehicle is running at a low
speed for an extended period, such as in heavy traffic. ■
Charging the 12-volt battery
The electricity stored in the 12-volt battery will discharge gradually even when the vehicle
is not in use, due to natural discharge and the draining effects of certain electrical appli-
ances. If the vehicle is left for a long time, the 12-volt battery may discharge, and the
hybrid system may be unable to start. (The 12-volt battery recharges automatically while
the hybrid system is operating.) ■
When the 12-volt battery is removed or discharged ●
In some cases, it may not be possible to unlock the doors using the smart access system
with push-button start when the 12-volt battery is discharged. Use the wireless remote
control or the mechanical key to lock or unlock the doors. ●
The hybrid system may not start on the first attempt after the 12-volt battery has
recharged but will start normally after the second attempt. This is not a malfunction.●
The power switch mode is memorized by the vehicle. When the 12-volt battery is
reconnected, the system will return to the mode it was in before the 12-volt battery was
discharged. Before disconnecting the 12-volt battery, turn the power switch off.
If you are unsure what mode the power switch was in before the 12-volt battery dis-
charged, be especially careful when reconnecting the 12-volt battery. ●
The power back door must be initialized. (  P. 1 3 4 )●
Make sure that the key is not inside the vehicle when recharging or replacing the
12-volt battery. The key may be locked in the vehicle if the alarm is activated. (  P. 88)5
6
7
8
9
10

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

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

610 9-1. Specifications
NX300h_U_OM78007U ■
Engine number
The engine number is stamped on
the engine block as shown.

Front 
Rear (AWD models)Engine Model 2.5 L 4-cylinder (2AR-FXE)
Ty p e 4-cylinder in line, 4-cycle, gasoline
Bore and stroke 3.54  3.86 in. (90.0  98.0 mm)
Displacement 152.2 cu.in. (2494 cm 3
)
Valve clearance (engine cold) Automatic adjustment
Drive belt tension Automatic adjustment
Fuel Fuel type Unleaded gasoline only
Octane Rating 87 (Research Octane Number 91) or higher
Fuel tank capacity (Reference) 14.8 gal. (56 L, 12.3 Imp.gal.)
Electric motor (traction motor) Ty p e Permanent magnet synchronous motor
Maximum output 105 kW
Maximum torque 199 ft•lbf (270 N•m, 27.5 kgf•m)
Ty p e Permanent magnet synchronous motor
Maximum output 50 kW
Maximum torque 103 ft•lbf (139 N•m, 14.2 kgf•m)

6119-1. Specifications
9
Vehicle specifications
NX300h_U_OM78007U * : 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.Hybrid battery (traction battery) Ty p e Nickel-Metal hydride battery
Vo l t a g e 7. 2 V/m o d u l e
Capacity 6.5 Ah (3HR)
Quantity 34 modules
Overall voltage 244.8 V
Lubrication system Oil capacity
(Drain and refill — reference
* )
With filter
Without filter 4.6 qt. (4.4 L, 3.9 Imp.qt.)
4.2 qt. (4.0 L, 3.5 Imp.qt.)