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ES300h_OM_OM33C75U_(U)7-2. Maintenance
Emission inspection and maintenance (I/M)
programs
The OBD system determines that a problem exists somewhere in the emission
control system. Your vehicle may not pass the I/M test and may need to be
repaired. Contact your Lexus dealer to service the vehicle.
●When the 12-volt battery is disconnected or discharged
Readiness codes that are set during ordinary driving are erased.
Also, depending on your driving habits, the readiness codes may not be com-
pletely set.
●When the fuel tank cap is loose
The malfunction indicator lamp comes on indicating a temporary malfunction
and your vehicle may not pass the I/M test.
The error code in the OBD system will not be cleared unless the vehicle is driven
40 or more times.
Contact your Lexus dealer to prepare the vehicle for re-testing.
Some states have vehicle emission inspection programs which include OBD
(On Board Diagnostics) checks. The OBD system monitors the operation of
the emission control system.
If the malfunction indicator lamp comes on
Your vehicle may not pass the I/M test in the following situations:
When the malfunction indicator lamp still remains on after several driv-
ing trips
If your vehicle does not pass the I/M test
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ES300h_OM_OM33C75U_(U)7-3. Do-it-yourself maintenance
7
Maintenance and care
Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the correct proce-
dure as given in these sections.
ItemsParts and tools
12-volt battery con-
dition (
→P. 4 6 1 )•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
(→ P. 4 5 9 )
• FMVSS No.116 DOT 3 or SAE J1703 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Engine/power con-
trol unit coolant level
(→ P. 4 5 7 )
• “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 coolant)
Engine oil level
(→ P. 4 5 3 )
• “Toyota Genuine Motor Oil” or equivalent
• Rag or paper towel
• Funnel (used only for adding engine oil)
Fuses (→ P. 4 8 3 )• Fuse with same amperage rating as original
Light bulbs
(→ P. 4 8 6 )
• Bulb with same number and wattage rating as original
• Phillips-head screwdriver
•Flathead screwdriver•Wrench
Radiator and con-
denser ( →P. 4 5 8 )
Tire inflation pres-
sure ( →P. 4 74 )• Tire pressure gauge• Compressed air source
Wa s h e r f l u i d
(→ P. 4 6 0 )• Water or washer fluid containing antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)
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ES300h_OM_OM33C75U_(U)7-3. Do-it-yourself maintenance
7
Maintenance and care
Engine compartment
■12-volt battery
→
P. 4 6 1
Wa s h e r f l u i d t a n k ( →P. 4 6 0 )
Fuse boxes ( →P. 4 8 3 )
Power control unit coolant
reservoir ( →P. 4 5 7 )
Engine oil level dipstick (→ P. 4 5 3 )
Engine oil filler cap ( →P. 4 5 4 ) Engine coolant reservoir
(→ P. 4 5 7 )
Brake fluid reservoir ( →P. 4 5 9 )
Power control unit coolant
radiator ( →P. 4 5 8 )
Electric cooling fans
Condenser ( →P. 4 5 8 )
Engine coolant radiator (→ P. 4 5 8 )1
2
3
4
5
6
7
8
9
10
11
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ES300h_OM_OM33C75U_(U)7-3. Do-it-yourself maintenance
7
Maintenance and care
12-volt battery
The 12-volt battery is located on the
right-hand side of trunk.
Remove the 12-volt battery cover.
Install the cover
Lift the tab to secure to the trunk
liner
Location
Removing the 12-volt battery cover
Installing the 12-volt battery cover
1
2
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ES300h_OM_OM33C75U_(U)7-3. Do-it-yourself maintenance
Make sure that the 12-volt battery terminals are not corroded and that there are
no loose connections, cracks, or loose clamps. Make sure that the terminal cov-
ers are secured over the battery terminals.
Te r m i n a l s
Hold-down clamp
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flammable and
explosive. Therefore, observe the following precautions before recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to disconnect the
ground cable.
●Make sure the power switch on the charger is off when connecting and disconnecting
the charger cables to the 12-volt battery.
■After recharging/reconnecting the 12-volt battery
●The hybrid system may not start. Follow the procedure below to initialize the system.Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system.
●Unlocking the doors using the smart access system with push-button start may not be
possible immediately after reconnecting the 12-volt battery. If this happens, use the
wireless remote control or the mechanical key to lock/unlock the doors.
●Start the hybrid system with the power switch in ACCESSORY mode. The hybrid sys-
tem may not start with the power switch turned off. However, the hybrid system will
operate normally from the second attempt.
●The power switch mode is recorded by the vehicle. If the 12-volt battery is reconnected,
the vehicle will return the power switch mode to the status it was in before the 12-volt bat-
tery was disconnected. Make sure to turn off the power switch before disconnect the 12-
volt battery. Take extra care when connecting the 12-volt battery if the power switch mode
prior to discharge is unknown.
If the system will not start even after multiple attempts at all methods above, contact your
Lexus dealer.
Exterior
1
2
1
2
3
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ES300h_OM_OM33C75U_(U)
4637-3. Do-it-yourself maintenance
7
Maintenance and care
WA R N I N G
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may produce
hydrogen gas which is flammable and explosive. To reduce the risk of death or serious
injury, take the following precautions while working on or near the 12-volt battery:
●Do not cause sparks by touching the 12-volt battery terminals with tools.
●Do not smoke or light a match near the 12-volt battery.
●Avoid contact with eyes, skin and clothes.
●Never inhale or swallow electrolyte.
●Wear protective safety glasses when working near the 12-volt battery.
●Keep children away from the 12-volt battery.
■Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-volt battery in
a garage or closed room where there is insufficient ventilation.
■How to recharge the 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may explode if charged
at a quicker rate.
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immediate medical
attention. If possible, continue to apply water with a sponge or cloth while traveling to
the nearest medical facility.
●If electrolyte gets on your skin
Wash the affected area thoroughly. If you feel pain or burning, get medical attention
immediately.
●If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the clothing and fol-
low the procedure above if necessary.
●If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention immedi-
ately.
■When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause gas (hydro-
gen) to enter the passenger compartment, causing a fire or explosion.
For replacement of the 12-volt battery, contact your Lexus dealer.
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ES300h_OM_OM33C75U_(U)7-3. Do-it-yourself maintenance
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is operating. Also, be sure
all accessories are turned off.
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ES300h_OM_OM33C75U_(U)7-3. Do-it-yourself maintenance
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Maintenance and care
Electronic key battery
●Flathead screwdriver
●Small flathead screwdriver
●Lithium battery CR2032
Take out the mechanical key.
Remove the cover.
To prevent damage to the key, cover the
tip of the screwdriver with a rag.
Remove the depleted battery.
Insert a new battery with the “+” termi-
nal facing up.
Replace the battery with a new one if it is depleted.
You will need th
e following items:
Replacing the battery
1
2
3