This MODE allows for the clearing and resetting of all DTCs (MODE $03), freeze frame data (MODE $02), readiness flag results (MODE $01), and test results values (MODEs $05 & $06).

When attempting to perform a Clearing of Diagnostic information, the Technician will always be asked: Do you wish to Continue?

The reason is that you may be clearing information that could help diagnose the problem. Or, clearing the Monitors could cause someone to fail a Smog Inspection.
MODE $04 does not clear learned or adaptive strategies.