THE MOTOR INDUSTRY OF JAPAN 2019

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Japan’s Test Cycles for Measuring Fuel Consumption and Exhaust EmissionsJapan not only promotes the international standardization of test cycles for measuring motor vehicle fuel consumption and CO2 and other emissions but has actively contributed to the development of the Worldwide Harmonized Light Vehicle Test Cycle (also referred to as the Worldwide Harmonized Light-Duty Test Cycle), or WLTC, under the United Nations’ World Forum for Harmonization of Vehicle Regulations. In line with that initiative, Japan is now in the process of replacing its JC08 test cycle for passenger cars and other non-heavy-duty vehicles with WLTC. WLTC incorporates three driving cycles: the “urban, rural and expressway modes,” as they are called in Japanese. The indication wherever necessary of fuel consumption rates measured in the three driving “modes” as well as their certified mean (i.e., average) rate has been required since October 2018.● COMPARISON OF THE JC08 TEST CYCLE AND WLTC FOR LIGHT VEHICLES● HOW LIGHT-VEHICLE FUEL CONSUMPTION RATES (EXAMPLES) ARE INDICATED IN JAPANMeasured on the basis of the JC08 test cycle01,600Time (sec)1,4001,2001,0008006004002001000102030405060708090(1) Fuel consumption rates are obtained on the basis of designated test conditions. In real-world on-road driving, rates will vary as a result of multiple factors (weather and traffic conditions, driving behavior, use of air conditioner, etc.).Vehiclespeed(km/h)The JC08 Test Cycle01,600Time (sec)1,4001,2001,000800600400200WLTCUrban modeRural modeExpressway modeFuel consumption rate (1) certifiedby the Ministry of Land, Infrastructure, Transport and Tourism21.4km/L(1) Fuel consumption rates are obtained on the basis of designated test conditions. In real-world on-road driving, rates will vary as a result of multiple factors (weather and traffic conditions, driving behavior, use of air conditioner, etc.).(2) WLTC is an international test cycle incorporating urban, rural and expressway driving cycles or “modes” with specific time durations designated for each mode.Urban mode: (Assumptions) Low-speed driving characterized by frequent stops and starts owing to numerous traffic signals and congestionRural mode: (Assumptions) Steady driving characterized by fewer stops and starts owing to fewer traffic signals and less congestion than in urban drivingExpressway driving mode: (Assumptions) High-speed driving typical of highway drivingFuel consumption rate (1) certifiedby the Ministry of Land, Infrastructure, Transport and Tourism20.4km/LMeasured on the basis of WLTCUrban mode (2) 15.2km/LRural mode (2) 21.4km/LExpressway mode (2) 23.2km/L(2)1000102030405060708090Vehiclespeed(km/h)Attention to the EnvironmentMeasuring Motor Vehicle Fuel Consumption and Emissions37