To add: the camera menu has no influence on focusing. The system is fully mechanical. I the case of (older) Elmar 135 lenses, the focusing mechanism is located inside the lens barrel and the square-looking "tongue" pushes against the roller at the top of the camera mount. If somebody removed it or if it does not move, the lens is probably irreparable, as there are no spare parts any more for this mechanism.
Unfortunately the use of a barrel from a donor lens is very nearly impossible too. The focus mechanism was filed down to tolerance to accommodate the variation of the individual lens heads. Therefore the lens number is scratched into the inside of the removable barrel, to ensure that the two would stay together. When buying such a lens it is essential to check for matching numbers.
The lens can be used on an M240 with EVF, however.