The Kings were trailing 2-1 in the final minute when they pulled their goalie for an extra attacker and managed to get the equalizer when Alec Martinez scored on the rebound of a Kyle Clifford shot.
But the deadlock was short-lived as the Red Wings responded almost immediately.
With time running out, Ericsson corralled the puck at the right point and unleashed a shot that Kings goalie Jonathan Quick slowed down, but it trickled between his legs and into the net for the decisive score.
Jimmy Howard turned aside a season-high 45 shots to earn the victory.
Anze Kopitar tallied and Quick finished with 28 saves for Los Angeles, which fell for the fourth time in five contests.