Merci, jai réussi à le faire finalement !

Voici ma solution, plus complexe que la tienne :

Sub RequetePMP()

' Connexion à la base

    Dim oConn As ADODB.Connection
    Dim rst As ADODB.Recordset
    Dim cmdCommand As ADODB.Command
   
    Dim connString As String
   
    connString = "Provider=MSDAORA.1;Server=XXXX;Data Source=XXXX;USER ID=XXXX;PASSWORD=XXXX"
    
    'Création de l'objet connection
    Set oConn = New ADODB.Connection
    oConn.ConnectionString = connString
    
    'Ouverture de la connexion
    oConn.Open
   
    'MsgBox "Connexion réussie"
  
    For i = 1 To 2000
   
        Cells(i, 1).Select
       
        If (Cells(i, 1).Value <> "") Then
       
            Set cmdCommand = New ADODB.Command
            Set cmdCommand.ActiveConnection = oConn
            With cmdCommand
                .CommandText = "Select AVC_0 from L3CGROUP.ITMMVT where ITMREF_0='" & Cells(i, 1).Value & "'"
                .CommandType = adCmdText
                '.Execute
            End With
           
            Set rst = New ADODB.Recordset
            Set rst.ActiveConnection = oConn
            'Sql = "Select AVC from L3CGROUP.ITMFACILIT where ITMREF='" & Cells(i, 1).Value & "';"
            rst.Open cmdCommand
           
            If rst.EOF = False Then
                Cells(i, 4).Value = rst.Fields(0)
            End If
        Else
            Cells(i, 4).Value = ""
        End If
       
        Set cmdCommand = Nothing
        Set rst = Nothing
       
    Next
   
    oConn.Close
   
End Sub

Merci de ton aide !!!