Apparatus and techniques are disclosed for aligning the operation of the ink jet printhead cartridges of a multiple printhead ink jet swath printer that includes a print carriage that is movable along a horizontal carriage scan axis, (b) first and second ink jet printhead cartridges supported by the movable carriage for printing onto a print media that is selectively movable along a vertical media scan axis, and (c) an optical sensor supported by the movable carriage. Correction of misalignment along the media scan axis is performed by adjusting the position of the nozzle array of one printhead cartridge relative to the position of the nozzle array of another printhead cartridge along the media scan axis. A movable printhead is supported on the print carriage of the printer and is moved relative to the carriage by a rotatable cam that is supported by the carriage fixedly attached to a cam lever. The cam is rotated by movement of the printhead carriage relative to a actuator arm that is selectively positioned in or out of the path traversed by the cam lever pursuant to movement of the printhead carriage. In particular, the cam is rotated by the movement of the carriage while the cam lever is engaged against the actuator arm.