Diesel particulate filters (DPF) require routine cleaning to remove ash that builds up over time. Most vehicles using a DPF system will have an on-board filter service monitor to indicate the filter condition and guide your filter cleaning schedule.
In ancient times the islands formed an independent kingdom. Chinese and Japanese sovereignty were successively forced on the archipelago from the 14th to the 19th century, and in 1879 the Ryukyus became an integral part of Japan. After the defeat of Japan (1945) in World War II, the United States took control of the islands.
The two concluded the secret Taft-Katsura Agreement, in which the United States acknowledged Japanese rule over Korea and condoned the Anglo-Japanese alliance of 1902. At the same time, Japan recognized U.S. control of the Philippines. In the years that followed, however, tensions rose over Japanese actions in northeast China and immigration to the United States. In 1905, the Japanese started to establish more formal control over South Manchuria by forcing China to give Japan ownership rights to the South Manchurian Railway.