There are a few reasons that the breathalyser is not switching on

  1.  Weak/Flat batteries.
    Try replacing with a brand new set of alkaline, non-heavy duty, non-rechargeable batteries.

  2. Calibration
    The unit may be due for calibration - especially if it hasn't been calibrated in the last 6 months. You can book your unit in for a calibration here.

  3. Chipset problem
    If you have replaced the batteries and/or if the unit is brand new or calibrated in the last 6 months then there could be an issue with the chipset. Please contact us by clicking on "New Support Ticket" above for further assistance.