Japanese auto supplier Tokai Rika Co. Ltd. has agreed to plead guilty and pay a $17.7 million fine for price-fixing, the U.S. Department of Justice said Tuesday.

The Nagoya, Japan-based company fixed the prices of heater control units that were sold to Toyota Motor Corp. in the U.S. between 2003 and 2010, the government said. Executives used code names and attempted to cover up the conspiracy by destroying documents when they learned the government was investigating.

Tokai Rika brings to nine the number of companies that have pleaded guilty in the department's ongoing investigation of price-fixing in the auto-supply industry. Eleven executives also have pleaded guilty and have been sentenced to pay fines and serve jail time.

Tokai Rika agreed to cooperate with the government's ongoing investigation into price-fixing as part of its plea deal.