Translate characters
INPUT;CHAR(1)
A variable that indicates to translate lowercase characters in the specified character string to uppercase characters. If this field contains a 1, the program translates lowercase characters of the string to uppercase before the scan using the coded character set identifier (CCSID) for the current job. If the translation cannot be done using the CCSID for the job, *CCSID37 is used. This does not change the user's data. Note that if 1 is specified and the pattern contains lowercase characters, a match never occurs. If 1 is specified, and the data to be searched contains noncharacter data (for example, packed or binary), unexpected results can occur.

Will heißen:
Die zu durchsuchende Zeichenkette wird in Großbuchstaben übersetzt und nicht die Suchfolge. Der Rest erklärt sich wohl von slbst.