javascript cannot access textbox value marked as "false"

<script language="javascript" type="text/javascript">

function showAlert() {

// document.getElementById('isMultifaults'). = '1';

document.getElementById("isMultifaults").value = "1";

// document.getElementById('isMultifaults').innerText = "wo riririr";

//form1.elements

alert("goes into javascript:" + document.getElementById("isMultifaults").value);

document.getElementById('fault2').style.display = 'table-row';

document.getElementById('fault2con').style.display = 'table-row';

document.getElementById('fault2rcon').style.display = 'table-row';

}

</script>

solution: <td style="display:none">

<asp:Textbox ID="isMultifaults" runat= "server" Text="0"/>

</td>