TOKYO, Sept 21 (Reuters) - Honda Motor Co (7267.T) said its car factories in Japan have been operating at 40% of capacity in August and September because of shortages of semiconductors and other components caused by the COVID-19 pandemic. Honda in a press release on its website said production in early October should rebound to 70% of capacity. "We are doing what we can to minimize the impact on production, but the situation remains unclear," the Japanese company said.