If the spinning starts, but the tonearm go up and down and the stops it's the steurepimpel. it's an easy fix, search for steuerpimpel.
if the platter do not move, or only tries to move, you have a problem with the power switch not engaging in automatic.
When you move the tonearm manually, the tonearm engages the power switch, when you move the tonearm to the rest position the tonearm disengages the power switch.
When you turn on with the start knob, the start knob engages the power switch, and it must remain engaged until the tonearm moves, and the the tonearm retains the power switch in the engaged position. usually this is only matter of sdjustement.
unfortunately i don't know the 1015 and the service manual is in german, so i can't help you more