P.M. BRIEFING : Toyota Plans to Build Testing Site on 12,000 Acres in Arizona

Toyota Motor Corp., Japan’s largest auto maker, said today that it plans to build a huge proving ground northwest of Phoenix to help develop cars and trucks mainly for the U.S. market.

The company’s California-based U.S. marketing arm, Toyota Motor Sales, said in a news release that it has filed papers for permission to build the complex about 45 miles northwest of Phoenix.

Construction is to begin next year with the complex becoming operational in 1993 if land purchases and permit applications proceed as expected, said company spokeswoman Deborah Sanchez Fair.

The complex will cover about 12,000 acres and include a 10-mile, high-speed oval, other shorter tracks with a variety of road conditions and an airstrip for flying in cars and trucks to be tested, she said.

The spokeswoman declined to estimate how much the complex will cost. In Monday’s editions, the New York Times quoted an unidentified automotive executive as saying it would be about $20 million.