Some erroneous info here. California DOES NOT check private RV towing weights. You do not go thru scales in CA. They are for commercial trucks only checking big rigs for Fed DOT legal weights.
Have been towing all manner of trailers and trucks for over 40 years. Have been stopped for other reasons but NEVER checked for weight.
That said, towing laws state if towing rig appears unsafe it can be removed from highway usage at the discretion of the LEO (CHP).
olddesertrider
Note; You will find at the few offroading areas in CA (especially the Glamis dunes) numerous rigs that are borderline overloaded with a few very overloaded and they are never checked by the LEOs. And there are very few accidents with these rigs and when they do happen it usually involves alcohol.