Page 630 of 846
629
GS350_OM_OM30D41U_(U)6-3. Do-it-yourself maintenance
6
Maintenance and care
Engine compartment
Fuse boxes ( →P. 6 6 1 )
Battery ( →P. 6 3 8 )
Engine oil level dipstick (→P. 6 3 1 )
Engine coolant reservoir (→P. 6 3 4 )
Engine oil filler cap ( →P. 6 3 2 ) Brake fluid reservoir
(→P. 6 3 7 )
Washer fluid tank ( →P. 6 4 1 )
Electric cooling fans
Condenser ( →P. 636)
Radiator ( →P. 636)1
2
3
4
5
6
7
8
9
10
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634
GS350_OM_OM30D41U_(U)
6-3. Do-it-yourself maintenance
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. 76 1 )
■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 engine coolant, contact your Lexus dealer.
■If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine 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.
Engine coolant
1
2
3
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7627-2. Steps to take in an emergency
GS350_OM_OM30D41U_(U)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.
Water can be used in an emergency if
coolant is unavailable.
Start the engine 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 system on and off
repeatedly. (The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately an d 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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7637-2. Steps to take in an emergency
GS350_OM_OM30D41U_(U)
7
When trouble arises
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.
●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 serious injury.
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 additives.
●Do not loosen the coolant inlet cap or the
coolant reservoir cap while the engine and
radiator are hot.
High temperature steam or coolant could
spray out.
GS350_OM_OM30D41U_(U).book Page 763 Monday, July 29, 2013 2:22 PM