* KOSPI index falls * Foreigners sell * Won weakens against U.S. dollar * S.Korea bond yields up SEOUL, March 19 (Reuters) - Round-up of South Korean financial markets: ** South Korea's KOSPI stock index started the week with losses as major auto shares declined after the U.S. regulator said it had opened a probe into airbag failure in vehicles from Hyundai Motor and Kia Motor . ** The Korean won edged down while bond yields rose. ** At 01:11 GMT, the KOSPI was down 16.75 points or 0.67 percent at 2,477.22. Hyundai Motor and Kia Motor fell as much as 4.8 percent and 2.8 percent, respectively, while Hyundai Mobis lost 5.4 percent. ** The won was quoted at 1,070.1 per dollar on the onshore settlement platform , 0.36 percent weaker than its previous close of 1,066.2. ** In offshore trading, the won was quoted at 1,070.5 per U.S. dollar, down 0.09 percent from the previous day, while in one-year non-deliverable forwards it was being transacted at 1,058.45 per dollar. ** MSCI's broadest index of Asia-Pacific shares outside Japan was down 0.35 percent after U.S. stocks ended the previous session with mild gains . Japanese stocks fell 1.24 percent. ** The KOSPI is up around 1.1 percent so far this year and up by 2.87 percent in the previous 30 days. ** The current price-to-earnings ratio is 12.10, the dividend yield is 1.28 percent and the market capitalisation is 1,242.04 trillion won. ** The trading volume during the session on the KOSPI index was 167,498,000 shares and out of the total traded issues of 877, the number of advancing shares was 287. ** Foreigners were net sellers of 47,414 million won worth of shares. ** The U.S dollar has risen 0.39 percent against the won this year. The won's high for the year is 1,056.67 per dollar on January 14 2018 and low is 1,098.4 on February 6 2018. ** In money and debt markets, March futures on three-year treasury bonds fell 0.03 points to 107.8. ** The Korean 3-month Certificate of Deposit benchmark rate was quoted at 1.65 percent, while the benchmark 3-year Korean treasury bond yielded 2.283 percent, higher than the previous day's 2.28 percent. (Reporting by Dahee Kim; Editing by Vyas Mohan)