Vehicle drive train with a parking lock

A vehicle drive train with an electric machine (EM), which outputs power to at least one vehicle wheel, may be configured with a parking lock (PS)having a parking lock gear arranged torque-transmittingly on an output shaft of the vehicle drive train, and a locking pawl which, in a locking position, is in toothed engagement with a tooth gap among tooth gaps of the parking lock gear. The electric machine (EM) may be assigned a test unit, by which, in a training routine, a gap detection (Δt) can be carried out, such that the test unit determines a rotor rotation angle position gap (α) of the electric machine rotor corresponding to the tooth gap.