Page 595 of 777
594 7-3. Do-it-yourself maintenance
RX350/RX350L_UEngine compartment
Washer fluid tank ( P. 603)
Engine oil filler cap ( P. 596)
Engine oil level dipstick
( P. 595)
Engine coolant reservoir
( P. 598) Battery ( P. 601)
Brake fluid reservoir ( P. 600)
Fuse box ( P. 625)
Radiator ( P. 599)
Condenser ( P. 599)
Electric cooling fans1
2
3
4 5
6
7
8
9
10
Page 599 of 777

598 7-3. Do-it-yourself maintenance
RX350/RX350L_U The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir when the engine is cold.
Reservoir cap
“FULL” line
“LOW” line If the level is on or below the “LOW”
line, add coolant up to the “FULL” line.
( P. 692)■
Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high qu ality 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 mixt ure of 50% coolant and 50% deionized water.
(Minimum temperature: -31 F [-35 C])
Canada:
“Toyota Super Long Life Cool ant” 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 coolant reservoir cap, drain cock and water
pump.
If you cannot find a leak, have your Lexus de aler test the cap and check for leaks in the
cooling system.Coolant 1
2
3
WARNING ■
When the engine is hot
Do not remove the engine coolan t reservoir cap and radiator cap.
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing serious injuries, such as burns.
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692 8-2. Steps to take in an emergency
RX350/RX350L_U Stop the vehicle in a safe place and tu rn 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, insp ect 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” line
“LOW” line
Radiator capIf your vehicle overheats The following may indicate that your vehicle is overheating. ●
The needle of the engine coolant temperature gauge ( P. 86) 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 comes out from under the hood.
Correction procedures 1
2
3
1
2
4
1
2
3
4
Page 695 of 777

694 8-2. Steps to take in an emergency
RX350/RX350L_U WARNING ■
To prevent an accident or injury 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 h ood, 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. ●
Do not loosen the radiator cap and the c oolant reservoir cap while the engine and
radiator are hot.
High temperature steam or coolant could spray out.
NOTICE ■
When adding engine coolant
Add coolant slowly after the engine has cool ed 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 foreig n matter (such as sand or dust etc.).●
Do not use any coolant additive.