This: https://www.thetaxadviser.com/issues/2012/may/hagy-banner-may2012.html
If the rental property is not rented and there is no personal use, very little guidance is provided as to the deductibility of expenses. One can argue that all of the expenses are deductible since there is no personal use, especially if extensive efforts to rent the property were made. Alternatively, since there are no rental or personal use days, the allowance of deductions ratio computed as “0 days rented divided by 0 days used” equals an undefined number. In this argument, it appears that only otherwise deductible mortgage interest and property taxes could be passed through to the partners.
Of course, they're talking about zero rental days here but, presumably, the property is still available for rent. I believe this would be applicable, if at all, to short-term rental properties (i.e., 7 days or less, sporadically throughout the year).
