Is there a time limit for challenging an ordinance based on procedural errors?

Yes. Wisconsin law places a significant time limitation on the ability of anyone to challenge the validity of an ordinance based on procedural errors. Specifically, Wis. Stat. sec. 889.04 provides that an ordinance entered or recorded in a city or village ordinance or record book pursuant to 62.09(11)(c) or 61.25(3) or printed in any newspaper, book, pamphlet, or other form purporting to be so published, entered or recorded by any city or village as a copy of its ordinance, bylaw, resolution or regulation is conclusive proof of the regularity of the adoption and publication of the ordinance, bylaw, resolution or regulation after three (3) years from the date of such publication, entry or recording.