Abstract: The present development relates to a closure cap for an equalizing reservoir of a motor vehicle cooling arrangement. The closure cap includes a cap body and a fill level sensor arranged on the cap body. The fill level sensor enables the fill level of the coolant inside the equalizing reservoir to be measured. The cap body may be disposed removably on the equalizing reservoir and typically closes off a filling opening of the equalizing reservoir. The configuration of the fill level sensor on the cap is extremely versatile, and can be used for a very wide range of equalizing reservoirs, which in principle can be closed with the same cover.