CDR file names have the following format/structure:

Position 1-4: Data year.
Position 5: Data program. "1" is for CISS.
Position 6-8: Three digit PSU number.
Position 9-11: Sequential Case Number for PSU.
Position 12: Embedded underscore as separator.
Position 13,14: Vehicle Number
Position 15-18: OPTIONAL. File type. 
	ACM=Air bag Control Module.
	PCM=Powertrain Control Module.