The code 15 comes up, when the calculated capability is just for information, and not for the overall result. This is the reason for example with single sided characteristics with a natural boundary, when the Capability-index is defined in the strategy as "information only"

Note: A true position is not threaten as a "characteristic with natural boundaries" and has own rules. 

The code 915 is coming up, when the result should not be given out. This is the reason for example with single sided characteristics with a natural boundary, when the Capability-index is defined in the strategy as "to be hidden"

Note: A true position is not threatened as a "characteristic with natural boundaries" and has own rules. 

Code “28” indicates that for positional tolerances, the superordinate characteristics cannot be assessed in this type of study.

For the subordinate characteristics, measured values of x- and y-coordinate, the calculation is provided.

The evaluation of "multivariate characteristics", and this includes positional tolerances, is only possible with Type-1 study. The why is explained in a separate topic. Link to: True Positions in MSA (and VDA5)