Canon EOS 90D DSLR Camera with 18-135mm Lens - Manual (Page 178)

178
Flash Function Settings
Clearing Flash Function Settings/Flash C.Fn Settings
M
1 Select [Clear settings].
2 Select the settings to be cleared.
 Select [Clear built-in fl ash set.] , [Clear
external fl ash set.] , or [Clear ext. fl ash
C.Fn set.] .
 On the confi rmation dialog, select [OK] .
Then the fl ash settings or Custom
Function settings will all be cleared.