By Lisa Twaronite, MarketWatch TOKYO (MarketWatch) -- The dollar edged down against its major counterparts in Asian trading Tuesday, though it remained in a relatively narrow range amid investors' caution ahead of this week's U.S. Federal Reserve meeting. The Bank of Japan unanimously voted to leave its unsecured overnight call loan rate unchanged at 0.1% Tuesday, as expected, and left its overall economic assessment unchanged. See full story on Bank of Japan. The dollar was at 96.80 yen, down from 97.15 yen in late North American trading on Monday. The dollar index (DXY 79.10, -0.16, -0.20%) , a measure of the greenback against a trade-weighted basket of currencies, was at 79.19, down from 79.365 late Monday. The euro traded at $1.4164, up from $1.4135 late Monday. Looking ahead, investors await the outcome of the Fed's monetary policy meeting on Tuesday and Wednesday. Analysts expect little change to officials' statement about leaving interest rates unchanged for an extended time. Read The Fed. The Fed is also widely expected to allow its program of buying up to $300 billion in Treasurys to expire when that amount is reached, likely sometime in September. Read story on Fed's Treasury purchases.

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