i have a Tsp truck that has no lift/lower, the truck drives fine. handset is coming up with code 59. has anyone out there ran into this?

side note, the contact tips are fine, the encoder is indexed and and has full sweep, when you give the lift comand the contacts do not pull in. checked the ossilator card and couldnt see any burnning. i know there is another card for the lift command but havent checked it yet

thanks