使用AJAX更改嵌入式Gmaps iFrame SRC

I'm trying to change the SRC of an iFrame using a URL retreived by AJAX from my backend database. I need the maps to change on click of a button.

The error showing inside the iFrame is " 404. That’s an error. The requested URL //embed was not found on this server. That’s all we know." Which makes me think the SRC isn't being changed properly.

Any help on this would be great!

Heres my setup:

<iframe id="HTMLGmapsSRC" src="" width="300" height="450" frameborder="0" style="border:0" allowfullscreen></iframe>

 var artgmaps = (imagesgmaps[index].replace(/\"/g, ""));
 $('#HTMLGmapsSRC').attr('src', artgmaps);

The JSON response has added backslashes however i've read this is normal?

I Used this method for the embed data in iframe.

$location = "Address which is get from the data base".

 <div id="show_map" style="display:block;">
        <address class="row"><?php echo $location;?></address>
  </div>

and use address tag for show map

$("address").each(function(){ 

    var embed ="<iframe width='100%' height='350' frameborder='0' scrolling='no'  marginheight='0' marginwidth='0'   src='https://maps.google.com/maps?&amp;q="+ encodeURIComponent( $(this).text() ) +"&amp;output=embed'></iframe>";
                                    $(this).html(embed);
    });