Obs is recalling 3 ricon wheelchair lifts which it installed on certain blue bird and Dodge Sprinter school buses. These vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard no. 404, "platform lift installations in motor vehicles." The anti-stow interlock may not detect the presence of a wheelchair or mobility aid user. The pressure sensing switch that detects the presence of weight on the platform was not adjusted to the necessary sensitivity level. The lift could stow even though someone or something is still on the lift.