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31
1-1. Hybrid system
1
Before driving
HS250h_U_75050U
Hybrid battery air ventThere is an air intake vent on the
side of the rear left seatback for
the purpose of cooling the hybrid
battery (traction battery). If the
vent become blocked, the hybrid
battery may overheat, leading to a
reduction in hybrid battery output.
Emergency shut off system When a certain level of impact is detected by the impact sensor, the
emergency shut off system blocks off the high voltage current and stops
the fuel pump to minimize the risk of electrocution and fuel leakage. If the
emergency shut off system activates, your vehicle will not restart. To
restart the hybrid system, contact your Lexus dealer.
Hybrid warning messageA message is automatically displayed when a malfunction occurs in the
hybrid system or an improper operation is attempted. If a warning message is shown on
the multi-information display, read
the message and follow the
instructions.
(→P. 5 1 2 )
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569
6-1. Specifications
6
Vehicle specifications
HS250h_U_75050U
Fuel information
■Fuel tank opening for unleaded gasoline
To help prevent incorrect fueling, your vehicle has a fuel tank opening that only
accommodates the special nozzle on unleaded fuel pumps.
■Gasoline quality
In very few cases, driveability problems may be caused by the brand of gasoline you
are using. If driveability problems persist, try changing the brand of gasoline. If this
does not correct the problem, consult your Lexus dealer.
■Gasoline quality standards
●Automotive manufacturers in the U.S.A., Europe and Japan have developed a
specification for fuel quality called the World-Wide Fuel Charter (WWFC),
which is expected to be applied worldwide.
●The WWFC consists of four categories that are based on required emission
levels. In the U.S., category 4 has been adopted.
●The WWFC improves air quality by lowering emissions in vehicle fleets, and
improves customer satisfaction through better performance.
■Recommendation of the use of gasoline containing detergent additives
●Lexus recommends the use of gasoline that contains detergent additives to
avoid the build-up of engine deposits.
●All gasoline sold in the U.S.A. contains detergent additives to clean and/or keep
clean intake systems.
You must only use unleaded gasoline in your vehicle.
Select octane rating 87 (Research Octane Number 91) or higher. Use of
unleaded gasoline with an octane rating lower than 87 may result in engine
knocking. Persistent knocking can lead to engine damage.
At minimum, the gasoline you use should meet the specifications of
ASTM D4814 in the U.S.A. and CGSB3.5-M93 in Canada.
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570
6-1. Specifications
HS250h_U_75050U
■Recommendation of the use of cleaner burning gasoline
Cleaner burning gasoline, including reformulated gasoline that contains oxygen-
ates such as ethanol or MTBE (Methyl Tertiary Butyl Ether) is available in many
areas.
Lexus recommends the use of cleaner burning gasoline and appropriately blended
reformulated gasoline. These types of gasoline provide excellent vehicle perfor-
mance, reduce vehicle emissions and improve air quality.
■Non-recommendation of the use of blended gasoline
●If you use gasohol in your vehicle, be sure that it has an octane rating no lower
than 87.
●Lexus does not recommend the use of gasoline containing methanol.
■Non-recommendation of the use of gasoline containing MMT
Some gasoline contains an octane enhancing additive called MMT (Methylcyclo-
pentadienyl Manganese Tricarbonyl).
Lexus does not recommend the use of gasoli ne that contains MMT. If fuel contain-
ing MMT is used, your emission control system may be adversely affected.
The malfunction indicator lamp on the instrument panel may come on. If this hap-
pens, contact your Lexus dealer for service.
■If your engine knocks
●Consult your Lexus dealer.
●You may occasionally notice light knocking for a short time while accelerating
or driving uphill. This is normal and there is no need for concern.
●Use only gasoline containing a maximum
of 10% ethanol.
DO NOT use any flex-fuel or gasoline that
could contain more than 10% ethanol,
including from any pump labeled E15, E30,
E50, E85 (which are only some examples
of fuel containing more than 10% ethanol).DO NOT use gasoline
containing more than
10% ethanol.
(15% ethanol)
(50% ethanol)
(85% ethanol)