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GS450h_OM_OM30D52U_(U)
6696-3. Do-it-yourself maintenance
6
Maintenance and care
■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 mixture of 50% coolant and 50% deionized
water. (Minimum temperature: -31 °F [-35 °C])
Canada:
“Toyota Super Long Life Coolant” is a mixture 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/power 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.
CAUTION
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or the cool-
ant inlet cap. ( →P. 800)
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 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.
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736
GS450h_OM_OM30D52U_(U)
7-2. Steps to take in an emergency
If you think something is wrong
●Fluid leaks under the vehicle.
(Water dripping from the air conditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge needle continually points higher
than normal.
●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 missing, stumbling 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 feeling, pedal almost touches the
floor
If you notice any of the following symptoms, your vehicle probably
needs adjustment or repair. Contact your Lexus dealer as soon as pos-
sible.
Visible symptoms
Audible symptoms
Operational symptoms
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800
GS450h_OM_OM30D52U_(U)
7-2. Steps to take in an emergency
If your vehicle overheats
■If the needle of the engine coolant temperature gauge enters the red
zone
Stop the vehicle in a safe place and turn off the air conditioning sys-
tem, 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.
●The needle of the engine coolant temperature gauge ( →P. 91) enters
the red zone or a loss of hybrid system power is experienced. (For
example, the vehicle speed does not increase.)
●“Hybrid System Overheat” ( →P. 762) is shown on the multi-informa-
tion display.
●Steam comes out from under the hood.
Correction procedures
1
2
3
1
2
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8017-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
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. 803)
Water can be used in an emer-
gency if engine coolant is unavail-
able.
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 operating by checking the fan
sound and air flow. If it is difficult to check these, turn the air conditioning sys-
tem on and off repeatedly. (The fans may not operate in freezing tempera-
tures.)
If the fans are not operating:
Stop the hybrid system immediatel y and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
4
1
2
3
4
5
6
7
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8027-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
■If “Hybrid System Overheat” is shown on the multi-information dis-
play
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 radi-
ator 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 emer-
gency if power control unit coolant
is unavailable.
1
2
3
1
2
4
1
2
3
5
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8037-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
7
When trouble arises
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.
■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 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
B-line (Target fill line)
6
1
2
3
1
2
3
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8047-2. Steps to take in an emergency
GS450h_OM_OM30D52U_(U)
CAUTION
■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 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 fan, which may lead to fin-
gers or clothing (especially a tie, a scarf or a muffler) getting 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 additives.
●Do not loosen the coolant inlet cap or the
coolant reservoir cap while the hybrid sys-
tem and radiator are hot.
High temperature steam or coolant could
spray out.
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Page 814 of 890
GS450h_OM_OM30D52U_(U)
8138-1. Specifications
8
Vehicle specifications
Cooling system
Capacity
Gasoline
engine9.9 qt. (9.4 L, 8.3 Imp.qt.)
Pow e r
control unit3.3 qt. (3.1 L, 2.7 Imp.qt.)
Coolant typeUse either of the following:• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based non-silicate, non-amine, non-nitrite, and non-borate
coolant with long-life hybrid organic acid tech-
nology
Do not use plain water alone.
Ignition system
Spark plug
Make
GapDENSO FK20HBR8
0.031 in. (0.8 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.
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