Patsy, Lenovo Thinkpad T430 fan error will not boot up, This error could be because the computers CPU fan plug/wires pinched/damaged/loose connection, fan is dirty/ faulty or problem with fan sensor on motherboard. Hope this helps, good luck.
Link below to forum that discusses your issue.
https://forums.lenovo.com/t5/ThinkPad-T400-T500-and-newer-T/Thinkpad-T430s-Fan-Error/td-p/1056265