Honda, Nissan, and Mitsubishi are considering sharing parts, with a focus on the car's brain, or engine control unit (ECU). This potential collaboration is part of a broader effort in Japan's auto industry to increase cooperation and standardize parts, possibly in response to growing competition from other countries. The extent of the partnership and its potential outcomes are still unclear, with some reports suggesting a deal between Honda and Nissan is near, while others speculate about possible future models.