Solo 401K and eligibility of spouse.

Hey guys, long time listener! My s corp (which I own 100% of,and my spouse is not an owner of the s-corp) sponsors a solo 401k in which we both receive contributions from our w2 wages. My question is if my wife soley owns an LLC which goes out and buys a boring business (I.e. a laundromat or a car wash) that might have employees, would she be able to still receive her contributions to the 401k? Thanks for all the nuggets of info guys.