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426
4-2. Maintenance
HS250h_U_75050U
General maintenance
Engine compartment
Tr u n k
ItemsCheck points
Brake fluidIs the brake fluid at the correct level?(→ P. 4 4 5 )
CoolantIs the engine coolant at the correct
level? (→ P. 4 4 2 )
Engine oilIs the engine oil at the correct level?
(→ P. 4 3 9 )
Exhaust systemThere should not be any fumes or
strange sounds.
Radiator/condenser
The radiator and condenser should
be free from foreign objects.
(→ P. 444)
Wa s h e r f l u i dIs there sufficient washer fluid?
(→ P. 446)
ItemsCheck points
12-volt batteryCheck the connections. ( →P. 4 4 7 )
Listed below are the general maintenance items that should be performed
at the intervals specified in the “Warranty and Service Guide” or “Owner’s
Manual Supplement”. It is recommended that any problem you notice
should be brought to the attention of your Lexus dealer or qualified service
shop for advice.
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4
Maintenance and care
HS250h_U_75050U
4-3. Do-it-yourself maintenance
Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the correct pro-
cedure as given in these sections.
ItemsParts and tools
12-volt battery condition ( →P. 4 4 7 )
•Grease
•Conventional wrench
(for terminal clamp bolts)
Brake fluid level ( →P. 4 4 5 )
• FMVSS No.116 DOT 3 or SAE
J1703 brake fluid
•Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/power control unit coolant
level (→ P. 4 4 2 )
• “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.
For the U.S.A.:
“Toyota Super Long Life Coolant”
is pre-mixed with 50% coolant and
50% deionized water.
For Canada:
“Toyota Super Long Life Coolant”
is pre-mixed with 55% coolant and
45% deionized water.
• Funnel (used only for adding cool- ant)
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4-3. Do-it-yourself maintenance
4
Maintenance and care
HS250h_U_75050U
Engine compartment
Engine coolant reservoir (→P. 4 4 2 )
Engine oil filler cap (→P. 4 3 9 )
Engine oil level dipstick (→P. 4 3 9 )
Power control unit coolant
reservoir ( →P. 4 4 2 )
Brake fluid reservoir (→P. 445)Fuse box ( →P. 4 6 9 )
Engine coolant radiator (→P. 444)
Power control unit coolant
radiator (→ P. 444)
Condenser ( →P. 444)
Electric cooling fans
Washer fluid tank (→P. 4 4 6 )
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4-3. Do-it-yourself maintenance
HS250h_U_75050U
CoolantThe coolant level is satisfactory if it is between the “FULL” and “LOW”
lines on the reservoir when the hybrid system is cold.
Engine coolant reservoir Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line. (→P. 5 6 4 )
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4-3. Do-it-yourself maintenance
4
Maintenance and care
HS250h_U_75050UPower control unit coolant reservoir
Reser voir cap
“FULL” line
“LOW” line
If the level is on or below the
“LOW” line, add coolant up to the
“FULL” line. (→P. 5 6 4 )
■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 radiators, 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 systems.
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5
When trouble arises
501
5-1. Essential information
HS250h_U_75050U
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact your Lexus dealer as soon as possible.
■Visible symptoms
● Fluid leaks under the vehicle
(Water dripping from the air conditioning after use is normal.)
● Flat-looking tires or uneven tire wear
● High engine coolant temperature warning light flashes or comes
on
■ Audible symptoms
● 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
■ Operational symptoms
● Engine missing, stumbling or running rough
● 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
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When trouble arises
553
5-2. Steps to take in an emergency
HS250h_U_75050UAfter the hybrid system has cooled
down sufficiently, check the engine
coolant level and inspect the cool-
ing system for leaks.
If the engine compartment cover
needs to be removed. (
→P. 4 3 8 )
Add engine coolant if necessary.
Water can be used in an emer-
gency if engine coolant is unavail-
able. ( →P. 5 6 4 )
Have the vehicle inspected at the nearest Lexus dealer as soon as possi-
ble.
■If “HYBRID SYSTEM OVERHEAT” is shown on the multi-informa-
tion display
Stop the vehicle in a safe place.
Stop the hybrid system (press the “POWER” switch once), and
then carefully lift the hood.
Wait until the hybrid system has
fully cooled down. When the sys-
tem has fully cooled down, check if
coolant has leaked from the radia-
tor core.
If a large amount of coolant leak-
age is found, contact your Lexus
dealer immediately.
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5-2. Steps to take in an emergency
HS250h_U_75050UCheck that the coolant level of the
power control unit is between the
“FULL” and “LOW” lines of the
reservoir tank.
“FULL” line
“LOW” line
If the coolant level of the power
control unit is insufficient, add
more coolant.
If power control unit coolant is
unavailable, water can be used as
an emergency substitute.
Restart the hybrid system (depress and hold the brake pedal, and
press the “POWER” switch once). Check that the “HYBRID
SYSTEM OVERHEAT” message has gone off.
If the warning message remains on, stop the hybrid system and
contact your Lexus dealer.
Have the vehicle inspected at the nearest Lexus dealer as soon as possi-
ble.
■Overheating
The following symptoms may occur when your vehicle is overheating:
●The high engine coolant temperature warning light comes on or flashes, or the
hybrid system output decreases.
●Steam comes out from the engine area.
●“HYBRID SYSTEM OVERHEAT” is displayed on the multi-information display.