Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
Call procПерехватКлавиш(KeyCode, Shift, Form.Name)
End Sub

Public Sub procПерехватКлавиш(KeyCode As Integer, Shift As Integer, frmname As String)
If KeyCode = vbKeyS And Shift = acCtrlMask Then
   MsgBox "CTRL+S" 'вставил для проверки работы
   DoCmd.Save acForm, frmname
End If
End Sub

Private Sub DataGrid1_KeyDown(KeyCode As Integer, Shift As Integer)
   
    CtrlDown = (Shift And vbCtrlMask) > 0
    If KeyCode = vbKeyS Then
        If CtrlDown Then
        Txt = "CTRL+S."
    End If
    MsgBox "You pressed " & Txt
    End If
End Sub

Dim CtrlDown, txt

Debug.Print "KeyKod:" & KeyCode
Debug.Print "Shift:" & Shift
    
CtrlDown = (Shift And acCtrlMask) > 0
    If CtrlDown Then
        If KeyCode = vbKeyS Then
            txt = "CTRL+S."
            MsgBox "You pressed " & txt
        End If
    End If