Page 510 of 668

5107-2. Steps to take in an emergency
GS350_200t_GS F_OM_OM30E87E_(EE)
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 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 engine
●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 any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional as soon as possible.
Visible s ymp toms
Audible symptoms
Operational symptoms
Page 527 of 668
5277-2. Steps to take in an emergency
7
When trouble arises
GS350_200t_GS F_OM_OM30E87E_(EE)
Indicates a malfunction in:• The SRS airbag system; or
• The seat belt pretensioner system
A buzzer also sounds.
→ Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and
equipped professional.
Indicates a malfunction in:
•The ABS; or
• The brake assist system
A buzzer also sounds.
→ Immediately stop the vehicle in a safe place and
contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Indicates that the engine coolant temperature is too high
A buzzer also sounds.
→ P. 5 9 6
(GS350/GS200t only)
Indicates a malfunction in the vehicle’s charging system.
→Immediately stop the vehicle in a safe place and
contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
Wa r n i n g m e s s a g eDetails/Actions
Page 596 of 668

5967-2. Steps to take in an emergency
GS350_200t_GS F_OM_OM30E87E_(EE)
If your vehicle overheats
●The needle of the engine coolant temperature gauge (→P. 108, 113) enters
the red zone or a loss of engine 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” is shown
on the multi-information display.
●Steam is coming from under the hood.
Stop the vehicle in a safe place and turn off the air conditioning system, and
then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the engine has cooled down sufficiently, inspect the hoses and radiator
core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, imme-
diately contact any authorized Lexus
dealer or repairer, or another duly quali-
fied and equipped professional.
The following may indicate that your vehicle is overheating.
Correction procedures
1
2
3
1
2
Page 597 of 668
5977-2. Steps to take in an emergency
7
When trouble arises
GS350_200t_GS F_OM_OM30E87E_(EE)
The coolant level is satisfactory if it is between the “FULL”/ “F” and “LOW”/ “L”
lines on the reservoir.Engine coolant reservoir
“FULL”/ “F”
“LOW”/ “L”
Coolant inlet cap
Intercooler coolant reservoir
XGS 200t
4
1
2
3
4
5
XGS350 XGS F
Page 599 of 668

5997-2. Steps to take in an emergency
7
When trouble arises
GS350_200t_GS F_OM_OM30E87E_(EE)
Start the engine and turn the air conditioning system on to check that the radi-
ator 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 system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately and contact any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
If the fans are operating:
Have the vehicle inspected at the nearest any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
■When adding engine coolant (GS350/GS200t)
Add coolant in accordance with the following procedure.
Remove caps A and B.
Add engine coolant through the inlet of cap A up to the “[AR/GR] B” line, and then
install cap A.
Add engine coolant through the inlet of cap B until it is full, and then install cap B.
GS200t only: When installing cap B, apply coolant to the O-ring on the end of cap B.
Cap A
Cap B
“[AR/GR] B” line (Target fill line)
6
7
1
2
3
GS350 GS200t
1
2
3
Page 600 of 668

6007-2. Steps to take in an emergency
GS350_200t_GS F_OM_OM30E87E_(EE)
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.
●Keep hands and clothing (especially a tie, a scarf or a muffler) away from the fans and
belts. Failure to do so may cause the hands or clothing to be caught, resulting in seri-
ous injury.
●GS350: Do not loosen the coolant inlet cap
or the engine coolant reservoir cap while the
engine and radiator are hot.
High temperature steam or coolant could
spray out.
●GS F: Do not loosen the engine coolant res-
ervoir cap while the engine and radiator are
hot.
High temperature steam or coolant could
spray out.
●GS200t: Do not loosen the coolant inlet cap,
the engine coolant reservoir cap or the inter-
cooler coolant reservoir cap while the engine
and radiator are hot.
High temperature steam or coolant could
spray out.
Page 601 of 668
6017-2. Steps to take in an emergency
7
When trouble arises
GS350_200t_GS F_OM_OM30E87E_(EE)
NOTICE
■When adding engine coolant
Add coolant slowly after the engine has cooled down sufficiently. Adding cool coolant
to a hot engine too quickly can cause damage to the engine.
■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.
Page 619 of 668