The accident -- Honda vs. BMW -- went down in one of L.A.'s busiest intersections ... Sepulveda and Santa Monica Boulevards, and Shaq happened to be driving by in the aftermath. We're told the big fella thought it looked bad enough that he should stop, and try to be of assistance. Y'know, in case a door needed to be ripped off or something.

Luckily, it turned out no one appeared to be seriously hurt. Some passersby saw Shaq on the scene, and thought he was in the accident, but he was really just a giant Samaritan.

We're told Shaq surveyed the situation, realized everyone was okay, shook a few hands ... and went on his way. No paramedics or cops were involved, just a tow truck.

No truth to rumors Shaq handed out cards for the General.