Toyota Motor Co (NYSE:TM) said on Monday that it plans to suspend all production of its vehicles in Japan until Wednesday March 16th.The Carmaker said the planned production halt at its 12 factories in the country would reduce output by 40,000 vehicles.The company produced over 234,000 cars in January in Japan, where it manufactures 38% of its cars.One major question is the condition of a plant operated jointly with Panasonic near Sendai, Japan, the city hardest hit by the quake and tsunami, which produces 200,000 EV batteries annually.This is a huge deal for the Prius model, already in tight supply and with sales up 70% year-over-year, as the car is only produced in Japan and currently has a commanding share of the market. If production is slow for an extended period of time, Toyota dealers will have a tough time holding on to potential buyers, who might start looking elsewhere at similar cars made by Toyota competitors.Shares of Toyota Motor are trading down 4.68% at $81.64.