diff --git a/modules/core_api/fsw/inc/cfe_es.h b/modules/core_api/fsw/inc/cfe_es.h
index edaf23745..70b11d108 100644
--- a/modules/core_api/fsw/inc/cfe_es.h
+++ b/modules/core_api/fsw/inc/cfe_es.h
@@ -984,7 +984,9 @@ CFE_Status_t CFE_ES_WriteToSysLog(const char *SpecStringPtr, ...) OS_PRINTF(1, 2
 **                                  XorOut: 0x0000
 **                          \arg \c CFE_MISSION_ES_CRC_32 - (not currently implemented)
 **
-** \return The result of the CRC calculation on the specified memory block, or error code \ref CFEReturnCodes
+** \return The result of the CRC calculation on the specified memory block.
+**         If the TypeCRC is unimplemented will return 0.
+**         If DataPtr is null or DataLength is 0, will return InputCRC
 **
 ******************************************************************************/
 uint32 CFE_ES_CalculateCRC(const void *DataPtr, size_t DataLength, uint32 InputCRC, uint32 TypeCRC);