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1-1. Hybrid system
1
Before driving
PRIUS v_OM_OM47840U_(U)
Hybrid battery (traction battery) air vent
There is an air intake vent under
the rear seat for the purpose of
cooling the hybrid battery (trac-
tion battery). If the vent becomes
blocked, the hybrid battery (trac-
tion battery) may overheat, lead-
ing to a reduction in hybrid
battery (traction battery) output.
Emergency shut off system When a certain level of impact is detected by the impact sensor, the
emergency shut off syst em blocks off the high voltage current and
stops the fuel pump to minimize t he risk of electrocution and fuel
leakage. If the emergency shut off sy stem activates, your vehicle will
not restart. To restart the hybrid system, contact your Toyota dealer.
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507
6-1. Specifications
6
Vehicle specifications
PRIUS v_OM_OM47840U_(U)
Fuel infor mation
■Fuel tank opening fo r 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 gas-
oline you are using. If driveability problems persist, try changing the brand of
gasoline. If this does not correct the problem, consult your Toyota dealer.
■ Gasoline quality standards
●Automotive manufacturers in the U.S.A., Europe and Japan have devel-
oped 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 emis-
sion 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 gaso line containing detergent additives
● Toyota 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 minimum detergent additives to
clean and/or keep clean intake systems, per EPA’s lowest additives con-
centration program.
● Toyota strongly recommends the use of Top Tier Detergent Gasoline. For
more information on Top Tier Detergent Gasoline and a list of marketers,
please go to the official website www.toptiergas.com.
You must only use unleaded gasoline in your vehicle.
Select octane rating 87 (Research Oc tane Number 91) or higher. Use
of unleaded gasoline with an octane rating lower than 87 may result
in engine knocking. Persistent kno cking 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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508 6-1. Specifications
PRIUS v_OM_OM47840U_(U)
■Recommendation of the use of cleaner burning gasoline
Cleaner burning gasoline, including reformulated gasoline that contains oxy-
genates such as ethanol or MTBE (Methyl Tertiary Butyl Ether) is available in
many areas.
Toyota recommends the use of cleaner burning gasoline and appropriately
blended reformulated gasoline. These types of gasoline provide excellent
vehicle performance, 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.
● Toyota 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 (Methyl-
cyclopentadienyl Manganese Tricarbonyl).
Toyota does not recommend the use of gasoline that contains MMT. If fuel
containing MMT is used, your emission control system may be adversely
affected.
The malfunction indicator lamp on the instrument cluster may come on. If
this happens, contact your Toyota dealer for service.
● Use only gasoline containing up to 15%
ethanol.
DO NOT use any flex-fuel or gasoline
that could contain more than 15% etha-
nol, including from any pump labeled
E30, E50, E85 (which are only some
examples of fuel containing more than
15% ethanol).DO NOT use gasoline
containing more than
15% ethanol.
(30% ethanol)
(50% ethanol)
(85% ethanol)