InvalidValueError บน google map platform แก้อย่างไร

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    <script>
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        apiKey: "AIzaSyCXYE4fp1gx0bPQXJbokpmO0eNBAwpaXCY",
        authDomain: "trackbus-fb460.firebaseapp.com",
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        projectId: "trackbus-fb460",
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        measurementId: "G-ED07MB2GKP"
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        firebase.initializeApp(firebaseConfig);
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</script>   

<script>
          var locations = [
          ['อาคารเรียนรวม1', 14.882821, 102.016159],
          ['อาคารเรียนรวม2', 14.881804, 102.014075 ],
          ['บขส.มอ', 14.877338, 102.022039 ],
          ['บรรณสาร', 14.877966, 102.014905 ],
          ['ส่วนกิจใหม่', 14.885597, 102.017975 ],
          ['หอ15', 14.890456, 102.017690 ],
          ['หอ16,หอ18', 14.893423, 102.013587 ],
          ['กาสะลองคำ', 14.896637, 102.012492 ],
          ['หอ13โซนล่าง', 14.899170, 102.011342 ],
          ['หอ13โซนบน', 14.898750, 102.011932 ],
          ['หอ7,8,9,10,11', 14.897586, 102.011095 ],
          ];

          var cars_count = 0;

// markers array to store all the markers, so that we could remove marker when any car goes offline and its data will be remove from realtime database...
          var markers = [];
          var maps;

          function initMap() {
            var mapOptions = {
              center: {lat: 14.889685 , lng: 102.018121},
              zoom: 14.2,
            }

            // mapC = new google.maps.Map(document.getElementById('map'), {
            //         zoom: 16,
            //         center: new google.maps.LatLng(14.889685, 102.018121),
            //         mapTypeId: 'terrain'
            // });
            
            maps = new google.maps.Map(document.getElementById("map"),mapOptions);
            
            var marker, i, info;
            for (i = 0; i < locations.length; i++) {
              marker = new google.maps.Marker({
              position: new google.maps.LatLng(locations[i][1], locations[i][2]),
              map: maps,
              title: locations[i][0],
              icon: "ico/png.png"
             
            });
            info = new google.maps.InfoWindow();
            google.maps.event.addListener(marker, 'click', (function(marker, i) {
              return function() {
                info.setContent(locations[i][0]);
                info.open(maps, marker);
              }
              })
              (marker, i));
              } 
              }

              
            function AddCar(data) {

              console.log(data.val());
              

              var icon = { // car icon
                  path: 'M29.395,0H17.636c-3.117,0-5.643,3.467-5.643,6.584v34.804c0,3.116,2.526,5.644,5.643,5.644h11.759   c3.116,0,5.644-2.527,5.644-5.644V6.584C35.037,3.467,32.511,0,29.395,0z M34.05,14.188v11.665l-2.729,0.351v-4.806L34.05,14.188z    M32.618,10.773c-1.016,3.9-2.219,8.51-2.219,8.51H16.631l-2.222-8.51C14.41,10.773,23.293,7.755,32.618,10.773z M15.741,21.713   v4.492l-2.73-0.349V14.502L15.741,21.713z M13.011,37.938V27.579l2.73,0.343v8.196L13.011,37.938z M14.568,40.882l2.218-3.336   h13.771l2.219,3.336H14.568z M31.321,35.805v-7.872l2.729-0.355v10.048L31.321,35.805',

                  scale: 0.7,
                  fillColor: "#ff0000", //<-- Car Color, you can change it 
                  fillOpacity: 1,
                  strokeWeight: 1,
                  anchor: new google.maps.Point(0, 5),
                  rotation: data.val().angle //<-- Car angle
              };

              var uluru = { lat: data.val().lat, lng: data.val().lng };

              var markerC = new google.maps.Marker({
                  position: uluru,
                  icon: icon,
                  map: maps
              });

              markers[data.key] = markerC; // add marker in the markers array...
              document.getElementById("cars").innerHTML = cars_count;
              }

              // get firebase database reference...
              var cars_Ref = firebase.database().ref();

              // this event will be triggered when a new object will be added in the database...
              cars_Ref.on('child_added', function (data) {
              cars_count++;
              AddCar(data);
              });

              // this event will be triggered on location change of any car...
              cars_Ref.on('child_changed', function (data) {
              markers[data.key].setMap(null);
              AddCar(data);
              });

              // If any car goes offline then this event will get triggered and we'll remove the marker of that car...  
              cars_Ref.on('child_removed', function (data) {
              markers[data.key].setMap(null);
              cars_count--;
              document.getElementById("cars").innerHTML = cars_count;
              });
</script>