Section 15275.1 - Schoolbus endorsement(a) Except as provided in subdivision (b), a schoolbus endorsement is valid only when the operator possesses or qualifies for a valid commercial driver's license with a passenger endorsement and possesses a schoolbus driver's certificate issued pursuant to Section 12517.(b) A schoolbus endorsement is valid without a schoolbus driver's certificate for an operator who is employed as a mechanic or a schoolbus driver-trainee if the schoolbus endorsement is restricted to operating a schoolbus when there is no pupil being transported.Amended by Stats 2005 ch 199 (AB 1748),s 4, eff. 1/1/2006Added by Stats 2004 ch 952 (AB 3049),s 15, eff. 1/1/2005, op. 9/20/2005.