Toyota Motor Co (NYSE:TM) has extended its Japanese shutdown of vehicle production until at least March 22nd, but will resume production of replacement parts for vehicles already on the market beginning tomorrow.Toyota said it was canceling weekend production and overtime in North America because the difficulty in shipping parts from damaged Japanese ports is leading to a parts shortage in that region. The company will restart the production of parts for foreign factories on March 21st, in an effort to alleviate the constricting supply chain.Rival Nissan Motor Co said it would resume vehicle production at two plants in the relatively unaffected south of the country by Friday, and would run until their supply chain was exhausted, stating they have enough inventory to run the plants for at least a couple of days.Shares of Toyota Motor are trading up 0.09% at $81.81.