To remove the steering wheel, first set the front wheels straight and release the steering lock with the ignition key. For models without an airbag, prise out the Mercedes-Benz emblem or horn pad from the center of the wheel, then slacken and remove the steering wheel retaining bolt. If there are no existing marks, mark the steering wheel and column shaft for alignment, then lift the steering wheel off the column splines, using gentle taps or twisting if it is tight. Inspect the horn contacts and contact ring for wear or damage. For models with an airbag, remove the airbag unit from the center of the steering wheel before proceeding to remove the steering wheel as previously described. When refitting, reverse the removal process, ensuring to coat the steering wheel horn contact ring with petroleum jelly and align the marks made during removal. For models with an airbag, if the contact unit was rotated, centralize it by pressing down and rotating anti-clockwise, then clockwise through three complete rotations. Ensure the contact unit wiring is correctly routed and that the locating peg engages with the recess in the contact unit as the wheel is refitted. Finally, tighten the steering wheel retaining bolt to the specified torque setting and refit the airbag unit.