2023 TOYOTA RAV4 PLUG-IN HYBRID coolant temperature

4827-3. Do-it-yourself maintenance
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL” line.
( P.578)
■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.
( P.580)
■Coolant selection
Only use “Toyota Super Long Life Coo- lant” 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.“Toyota Super Long Life Coolant” is a
mixture of 50% coolant and 50% deion- ized water. (Minimum temperature: -35°C [-31°F])
For more details about coolant, contact any authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer.
■If the coolant level drops within a short time of replenishing
Visually check the radiators, hoses,
engine/power control unit coolant reser- voir caps, drain cock and water pump.If you cannot find a leak, have any
authorized Toyota retailer or Toyota
authorized repairer, or any reliable repairer, 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 condition, have your vehicle
inspected by any authorized Toyota
retailer or Toyota authorized
repairer, or any reliable repairer.
C
A
B
C
WARNING
■When the hybrid system is hot
Do not remove the engine/power con- trol 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 mix-ture 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 prevent it from damaging parts or
paint.
Checking the radiator and
condenser

483
7
7-3. Do-it-yourself maintenance
Maintenance and care
Without level gauge
Type A: If any washer does not
work, the washer tank may be
empty. Add washer fluid.
Type B: If any washer does not
work or the warning message
appears on the multi-information
display, the washer tank may be
empty. Add washer fluid.
With level gauge
If the washer fluid level is at “LOW”,
add washer fluid.
■Using the gauge (if equipped)
The washer fluid level can be checked
by observing the position of the level on the liquid-covered holes in the gauge.
If the level falls below the second hole
from the bottom (the “LOW” position), refill the washer fluid.
Current fluid level
WARNING
■When the hybrid system is hot
Do not touch the radiator or con-
denser as they may be hot and cause serious injuries, such as burns.
■When the electric cooling fan is operating
Do not touch the engine compart-
ment.
With the power switch in ON, the electric cooling fan 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 cool- ing fan or radiator grille.
Checking and adding the
washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the hybrid system is hot or operating as
washer fluid contains alcohol and may catch fire if spilled on the hybrid system, etc.
A

5328-2. Steps to take in an emergency
Wheel nut wrench can be purchased
at any authorized Toyota retailer or Toyota authorized repairer, or any reli-able repairer.
 Fluid leaks under the vehicle
(Water dripping from the air con-
ditioning after use is normal.)
 Flat-looking tires or uneven tire
wear
 High coolant temperature warn-
ing light flashes or come on
 Changes in exhaust sound
 Excessive tire squeal when cor-
nering
 Strange noises related to the
suspension system
 Pinging or other noises related to
the hybrid system
 Engine missing, stumbling or
running roughly
 Appreciable loss of power
WARNING
Observe the following precautions. Failure to do so may result in death or serious injury.
■While towing
●When towing using cables or
chains, avoid sudden starts, etc. which place excessive stress on the towing eyelets, cables or chains.
The towing eyelets, cables or chains may become damaged, bro-ken debris may hit people, and
cause serious damage.
●Vehicles with steering lock function:
Do not turn the power switch off. There is a possibility that the steer-ing wheel is locked and cannot be
operated.
■Installing towing eyelets to the
vehicle
Make sure that towing eyelets are installed securely. If not securely
installed, towing eyelets may come loose during towing.
NOTICE
■To prevent damage to the vehicle during emergency towing
Do not secure cables or chains to the suspension components.
If you think something is
wrong
If you notice any of the follow-
ing symptoms, your vehicle
probably needs adjustment or
repair. Contact any authorized
Toyota retailer or Toyota
authorized repairer, or any reli-
able repairer as soon as possi-
ble.
Visible symptoms
Audible symptoms
Operational symptoms

535
8
8-2. Steps to take in an emergency
When trouble arises
■Charging system warning light
■High coolant temperature warning light* (warning buzzer)
*: This light illuminates on the multi-information display with a message.
■Hybrid system overheat warning light* (warning buzzer)
*: This light illuminates on the multi-information display with a message.
■Low engine oil pressure warning light* (warning buzzer)
*: This light illuminates on the multi-information display with a message.
Warning lightDetails/Actions
Indicates a malfunction in the vehicle’s charging sys-
tem
 Immediately stop the vehicle in a safe place
and contact any authorized Toyota retailer or
Toyota authorized repairer, or any reliable
repairer.
Warning lightDetails/Actions
Indicates that the engine is overheating
 Immediately stop the vehicle in a safe place.
Handling method ( P.578)
Warning lightDetails/Actions
Indicates that the hybrid system has overheated
 Stop the vehicle in a safe place.
Handling method ( P.578)
Warning lightDetails/Actions
Indicates that the engine oil pressure is too low
 Immediately stop the vehicle in a safe place
and contact any authorized Toyota retailer or
Toyota authorized repairer, or any reliable
repairer.

5788-2. Steps to take in an emergency
■If the high coolant temperature
warning light comes on,
flashes or “Engine Coolant
Temp High Stop in a Safe
Place See Owner’s Manual” is
shown on the multi-informa-
tion display
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.
NOTICE
■When handling jumper cables
When connecting the jumper cables,
ensure that they do not become entangled in the cooling fan, etc.
■To prevent damaging the vehicle
The exclusive jump starting terminal is to be used when charging the 12-
volt battery from another vehicle in an emergency. It cannot be used to jump start another vehicle.
If your vehicle overheats
The following may indicate that
your vehicle is overheating.
 The high coolant temperature
warning light ( P.183) comes
on or flashes, or a loss of
hybrid system power is experi-
enced. (For example, the vehi-
cle speed does not increase.)
 “Engine Coolant Temp High
Stop in a Safe Place See
Owner’s Manual” or “Hybrid
System Overheated Output
Power Reduced” is shown on
the multi-information display.
 Steam comes out from under
the hood.
Correction procedures

579
8
8-2. Steps to take in an emergency
When trouble arises
3 After the hybrid system has
cooled down sufficiently, inspect
the hoses and radiator core
(radiator) for any leaks.
Radiator
Cooling fan
If a large amount of coolant leaks, immediately contact any authorized Toyota retailer or Toyota authorized
repairer, or any reliable repairer.
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
engine coolant is unavailable. If water was added in an emergency,
have the vehicle inspected at any
authorized Toyota retailer or Toyota authorized repairer, or any reliable repairer as soon as possible.
6 Start the hybrid system and turn
the air conditioning system on to
check that the radiator cooling
fan operates and to check for
coolant leaks from the radiator
or hoses.
The fan operates when the air condi- tioning system is turned on immediately
after a cold start. Confirm that the fan is operating by checking the fan sound and air flow. If it is difficult to check
these, adjust the temperature control switch to “LO” and turn the “A/C” switch ON and OFF. After this, turn the air
conditioning system on and off repeat- edly. (The fan may not operate in freez-ing temperatures.)
7 If the fan is not operating:
Stop the hybrid system immedi-
ately and contact any authorized
Toyota retailer or Toyota autho-
rized repairer, or any reliable
repairer.
If the fan is operating:
Have the vehicle inspected at
the nearest authorized Toyota
retailer or Toyota authorized
repairer, or any reliable repairer.
A
B
A
B
C

581
8
8-2. Steps to take in an emergency
When trouble arises
again and check the multi-infor-
mation display.
If the message does not disappear:
Stop the hybrid system and contact any authorized Toyota retailer or Toyota authorized repairer, or any reliable
repairer. 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
frequently, contact any authorized Toyota retailer or Toyota authorized repairer, or any reliable repairer.
WARNING
■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 compartment may be very
hot.
●After the hybrid system has been
turned off, check that the “READY” indicator is off.When the hybrid system is operat-
ing, the gasoline engine may auto- matically 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 clothing (especially a tie, a scarf or a muffler) getting caught, result-ing 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 con-trol 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 dam- age to the hybrid system.
■To prevent damage to the cool-ing system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust, etc.).
●Do not use any coolant additive.

619Alphabetical Index
Operation ................................... 282
Emergency, in case of
If a warning buzzer sounds ........ 534
If a warning light turns on ........... 534
If a warning message is displayed
................................................. 544
If the 12-volt battery is discharged
................................................. 573
If the electronic key does not operate
properly.................................... 571
If the fuel filler door cannot be
opened..................................... 570
If the hybrid system will not start 568
If the vehicle is submerged or water
on the road is rising ................. 527
If you have a flat tire........... 548, 559
If you lose your keys .................. 570
If you think something is wrong.. 532
If your vehicle becomes stuck .... 582
If your vehicle has to be stopped in
an emergency .......................... 526
If your vehicle needs to be towed
................................................. 529
If your vehicle overheats ............ 578
Emergency brake signal .............. 416
Emergency flashers ..................... 526
Emergency tire puncture repair kit
..................................................... 548
Energy monitor ............................. 226
Engine
Compartment ............................. 479
Exhaust gas precautions.............. 47
Hood .......................................... 476
How to start the hybrid system... 310
Identification number.................. 585
If the hybrid system will not start 568
If your vehicle has to be stopped in
an emergency .......................... 526
Overheating ............................... 578
Power switch .............................. 310
Engine coolantCapacity ..................................... 588
Checking .................................... 481
High coolant temperature warning
light .......................................... 535
Preparing and checking before win-
ter ............................................. 422
Warning light .............................. 535
Engine coolant temperature 187, 193
Engine oil
Capacity ..................................... 587
Checking .................................... 479
Preparing and checking before win-
ter ............................................. 422
Warning light .............................. 535
EPS (Electric Power Steering)
Function ..................................... 416
Warning light .............................. 536
EV/HV mode selection switch........ 86
EV driving range ........................... 103
EV mode ..........................................85
Exhaust gas precautions ............... 47
Extended Headlight Lighting system
..................................................... 327
F
Flat tire ................................... 548, 559
Tire pressure warning system .... 488
Floor mats ....................................... 32
Fluid
Brake .......................................... 590
Hybrid transmission.................... 589
Rear differential .......................... 589
Washer ....................................... 483
Fog lights
Replacing light bulbs ..................516
Switch......................................... 331
Footwell lights............................... 443
Front fog lights
Replacing light bulbs ..................516
Switch......................................... 331
Front passenger’s seat belt reminder