JS (внутри protected/widgets/filterPanel/views/ajax_filter_panel.php)

<script>
    $.ajax('/api/get-filters', {
        method: 'POST',
        data: {
            dokRazdelId: "<?= $dokRazdelId ?>",
            filterRaw: "<?= $filterRaw ?>",
            priceFrom: "<?= $priceFrom ?>",
            priceTo: "<?= $priceTo ?>",
            forAllCars: "<?= $forAllCars ?>",
            <?= '"', DokVitrinaFilter::DOK_VITRINA_FILTER, '"' ?>: "<?= $dokVitrina ?>"
        },
        success: function (data) {
            if (data && data !== null && data !== undefined) {
                document.querySelector('.catalog__filter-column .filters').html(data);
            }
        },
        beforeSend: function () {
            document.querySelector('.catalog__filter-column .filters')
                .classList.add('filters-ajax-loader')
                .prepend('<div class="filter-overlay filter-overlay_show"><div></div></div>')
        },
        complete: function (data) {
            document.querySelector('.catalog__filter-column .filter-overlay.filter-overlay_show').remove();
            document.querySelector('.catalog__filter-column .filters')
                .removeClass('filters-ajax-loader');

            setTimeout(function () {
                setFilterState(true);
            }, 200)
        }
    });
</script>