How does ACF2 translates a RACROUTE class to a type code and then uses that type code to look for rules to be used in validation.
will show the order that ACF2 will search the in storage CLASMAP table. The first instance found for a class will show the type code to be used.
SHOW CLASMAP ... CPSMXMP SAF 44 11 CRYPTOZ CRY 246 578 CSFKEYS CSK 73 EXT 98 CSFKEYS SAF 73 98 ...
In this listing, a new CLASMAP was added for CSFKEYS. The EXT means "external" which is a user defined addition. So for this list, class CSFKEYS will use type code CSK, not the default shipped with ACF2, SAF.
If there is no default type code defined for a resource class, CA ACF2 will use the first 3 characters of the resource class as the type code.