{addjs file="{$mod_js}jquery.filter.js" basepath="root"}

{addjs file="jquery.filter.js"}

/modules/catalog/view/js/jquery.filter.js

/templates/Ваша тема/resource/js/jquery.filter.js

$('.filter .cb, .filter .yesno').styler(); //Вот так у Вас было

$('.filter .cb, .filter .yesno').styler(); 

$('input').styler('destroy');

<li>
                        <input class="checkbox" type="checkbox" checked name="bfilter[brand][]" value="1" class="cb" id="cb_1_">
                        <label for="cb_1_"><span></span>Acer</label>
                    </li>
                                        <li>
                        <input class="checkbox" type="checkbox" checked name="bfilter[brand][]" value="2" class="cb" id="cb_2_">
                        <label for="cb_2_"><span></span>Apple</label>
                    </li>

                <ul class="propsContent">
                    {foreach $brands as $brand}
                    <li>
                        <input class="checkbox" type="checkbox" name="bfilter[brand][]" value="{$brand.id}" class="cb" id="cb_{$brand.id}_{$smarty.foreach.i.iteration}">
                        <label for="cb_{$brand.id}_{$smarty.foreach.i.iteration}">{$brand.title}</label>
                    </li>
                    {/foreach}
                </ul>
        
<script type="text/javascript">
 $(document).ready(function(){
            $('.checkbox').change(function(){                    
                $('input[name="' + $(this).attr('name') +'"]').not(this).removeAttr('checked');  
            });           
        });

 </script>

         <script>
$('.checkbox').change(function(){
    $('input[name="' + $(this).attr('name') +'"]').removeAttr('checked');
    $(this).prop('checked', true);
});
 </script>