asp.net core jquery not functioning when ddl is empty

Question

I have a select and a textbox handled by a jquery. Basically, if I select a value from ddl, the textbox became disabled and if I enter text in the textbox, the ddl became disabled. The problem I have is: If the ddl is empty, the jquery does not work. How can I fix this?

  

<div class="row no-gutters" onchange="funcLocation()">
            <div class="col-md-2">
                <label class="form-control text-white" style="background-color:mediumorchid;">Location </label>
            </div>
            @if (Model.RALocation == true)
            {
                <div class="col-md-3">
                    <select id="LocS" class="form-control border-danger" asp-items="@Model.SelectLocation">
                        <option value="">--Select Location--</option>
                    </select>
                </div>
                <span class="text-danger ml-2 mr-2">OR</span>
            }
            <div class="col-md-3">
                <input id="LocT" class="form-control" placeholder="Enter New Location" />
                <input id="loc" asp-for="RiskAssessmentMain.Location"  />
            </div>
        </div>

 

function funcLocation() {
            var data1 = $("#LocS :selected").text();
            var data2 = $("#LocT").val();
            if (data2.length > 0) {
                $("#LocS").attr("disabled", true);
                $("#loc").val(data2);
            }
            else {
                $("#LocS").attr("disabled", false);
            }
            if (data1 != "--Select Location--") {
                $("#LocT").empty();
                $("#LocT").attr("disabled", true);
                $("#loc").val(data1);
            }
            else {
                $("#LocT").attr("disabled", false);
            }
        }