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When trouble arises
7-2. Steps to take in an emergency
If your vehicle overheats
●The needle of the engine coolant temperature gauge ( P. 86) enters the red
zone or a loss of hybrid system power is experienced. (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 Reduced Output Power” ( P. 406) is shown on
the multi-information display.
●Steam comes out from under the hood.
■If the needle of the engine coolant temperature gauge enters the red zone
or “Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” 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
cooling system for 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.
Correction procedures
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4587-2. Steps to take in an emergency
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The coolant level is satisfactory if it is between the “FULL” and “LOW” lines
on the reservoir.Reservoir
“FULL”
“LOW”
Coolant inlet cap
Add coolant if necessary.
( P. 4 6 0 )
Water can be used in an emergency
if engine 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.
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4597-2. Steps to take in an emergency
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7
When trouble arises
■If “Hybrid System Overheated Reduced Output Power” is shown on the
multi-information displayStop 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”
“LOW”
Add coolant if necessary.
Water can be used in an emergency
if power control unit coolant is
unavailable.
Start the hybrid system and check for 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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4607-2. Steps to take in an emergency
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■When adding coolant
Add coolant in accordance with the following procedure.
Remove caps A and B.
Add coolant through the inlet of cap A up to the “[GR-HV] B” line, and
then install cap A.
Add coolant through the inlet of cap B until it is full, and then install cap B.
Cap A
Cap B
“[GR-HV] B” line (Target fill line)1
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3
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4617-2. Steps to take in an emergency
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When trouble arises
WA R N I N G
■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 of f, check that the indicator on the power
switch and the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may automatically 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.
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.
●Do not loosen the coolant inlet cap or the
coolant reservoir cap while the hybrid system
and radiator are hot.
High temperature steam or coolant could
spray out.
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7-2. Steps to take in an emergency
If the vehicle becomes stuck
Stop the hybrid system. Set the parking brake and shift the shift lever to P.
Remove the mud, snow or sand from around the rear wheels.
Place wood, stones or some other material under the rear wheels to help pro-
vide traction.
Restart the hybrid system.
Shift the shift lever to D or R and release the parking brake. Then, while exer-
cising caution, depress the accelerator pedal.
■When it is difficult to free the vehicle
Carry out the following procedures if the tires spin or the vehicle becomes
stuck in mud, dirt or snow:
Press to turn off TRAC. ( P. 2 6 8 )
WA R N I N G
■When attempting to free a stuck vehicle
If you choose to push the vehicle back and forth to free it, make sure the surrounding
area is clear to avoid striking other vehicl es, objects or people. The vehicle may also
lunge forward or lunge back suddenly as it becomes free. Use extreme caution.
■When shifting the shift lever
Be careful not to shift the shift lever with the accelerator pedal depressed.
This may lead to unexpected rapid accelerati on of the vehicle that may cause an acci-
dent resulting in death or serious injury.
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4637-2. Steps to take in an emergency
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7
When trouble arises
NOTICE
■To avoid damaging the transmission and other components
●Avoid spinning the rear wheels and depressing the accelerator pedal more than nec-
essary.
●If the vehicle remains stuck even after these procedures are performed, the vehicle
may require towing to be freed.
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4647-2. Steps to take in an emergency
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