Load modals as WordPress template parts via AJAX

load-modal.js

$( function() {
	
	var loadModal = function( modal ) {
		
		$.post(
			pinwheel_modals.ajax_url,
			{
				action: 'load_modal',
				modal:  modal
			},
			/* Handle the response! */
			function ( response ) {
				
				if ( 0 != response ) {
					
					modal = $.parseHTML( response );
					
					/* Add the modal to the body. */
					$( 'body' ).append( modal );
					
					/* Take various actions when the modal is added. */
					$( modal ).addClass( 'modal-show' );
					$( 'body' ).addClass( 'has-modal' );
					
				}
				
			}
		);
		
	}
} );

load-modal.php

/**
 * Load a requested modal via AJAX.
 * 
 * @since 1.0.0
 * 
 * @return void
 */
function pinwheel_ajax_load_modal() {
	
	ob_start();
	
	get_template_part( 'parts/modal', $_POST['modal'] );
		
	$modal = ob_get_clean();
	
	if ( $modal ) {
		echo $modal;
	} else {
		echo 0;
	}
	
	die();
}
add_action( 'wp_ajax_load_modal',        'pinwheel_ajax_load_modal' );
add_action( 'wp_ajax_nopriv_load_modal', 'pinwheel_ajax_load_modal' );

load-on-click.js

/* Load a modal when any element with a modal specified is clicked */
$( '[data-modal]' ).on( 'click', function( e ) {
	
	e.preventDefault();
	
	var modal = $( this ).data( 'modal' );
	
	loadModal( modal );
	
} );

I get this error: pinwheel_modals :(

Modals are not showing.