Excepting only when the vehicles are actually engaged in the delivery or receiving of merchandise or cargo within the prohibited area, no person shall park or leave unattended a motor truck, semi-trailer or other motor vehicle with trailer attached on any streets within a business district. When actually receiving or delivering merchandise or cargo, the vehicle shall be stopped or parked in a manner which will not interfere with other traffic. The provisions of this section do not apply to pick-up, light delivery or panel delivery trucks.
(Iowa Code § 321.236(1)) (1999 Code, § 69.09) Penalty, see § 79.99