Hi,

The only problem i could observe is that there are 1:, 2:, etc. in the provided data source which make it invalid array.

Below is a working sample:

    const comboBox = document.querySelector("jqx-combo-box");

    const vehileBrands = [{ id: 272, brand: 'GPS_TR08' },
    { id: 2, brand: 'GPS_CONCOX_GT06MDF' },
    { id: 3, brand: 'GPS_CONCOX_GT06' },
    { id: 4, brand: 'GPS_CONCOX_GT07' },
    { id: 5, brand: 'GPS_CONCOX_GT08' },
    { id: 6, brand: 'GPS_CONCOX_GT700' },
    { id: 7, brand: 'GPS_CONCOX_GT710' },
    { id: 8, brand: 'GPS_CONCOX_GT800' },
    { id: 9, brand: 'GPS_CONCOX_GT300' },
    { id: 10, brand: 'GPS_CONCOX_GT03C' },
    { id: 11, brand: 'GPS_CONCOX_GT02' },
    { id: 12, brand: 'GPS_CONCOX_GT02D' },
    { id: 13, brand: 'GPS_CONCOX_TR02' },
    { id: 14, brand: 'GPS_CONCOX_TR06' },
    { id: 15, brand: 'GPS_CONCOX_GK310' },
    { id: 16, brand: 'GPS_CONCOX_GK309E' },
    { id: 17, brand: 'GPS_CONCOX_GS503' },
    { id: 30, brand: 'GPS_CONCOX_HVT001' }
    ];

    comboBox.valueMember = "id";
    comboBox.displayMember = "brand";
    comboBox.dataSource = vehileBrands;
    comboBox.onchange = (event) => {
        console.log(event.detail);
    }

Regards,
Markov