Customer support


Welcome to CTEK and thank you for being a valued customer.

We are here to help and in this section you will find FAQs, troubleshooting, warranty information and video tutorials. If you can’t find what you are looking for, please contact us.

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Top 10 FAQ

  • D250SE: How can I tell if D250SE is working?
    See answer

    Please refer to the manual "D250SE Function indications" for explantion of light sequence.

  • D250SE: Can I use D250SE for lithium batteries?
    See answer

    Yes it works both with lead-acid and lithium (12V LiFePO₄) batteries.

  • CT5 START/STOP: What do the three stages on the charger mean?
    See answer

    Check mode means that the charger is checking the battery’s state of health and preparing to charge. If the battery is in good condition, the Check stage doesn't take more than a few moments.
    The Charge mode LED shows while the charger is filling the battery, and Care shows when the battery is fully charged and the charger has automatically switched over to maintenance charging.

  • CTX BATTERY SENSE: There are three Bluetooth classes. Which does Battery Sense belong to?
    See answer

    BATTERY SENSE is Class 2.

  • CTX BATTERY SENSE: Can I update manually?
    See answer

    Yes, you can update manually by using "Pull to refresh".
    ("Pull to refresh" = Swipe your finger downwards over the screen in list mode)

  • CTX BATTERY SENSE: Why does background updating not work?
    See answer

    The app can be shut down if your phone is low on memory, for example. It's a good idea to activate the function in the app that notifies you if it hasn't been able to update during the last seven days.

  • Charger functions, Charger settings, Batteries, General, PRO25S, PRO25SE, PRO15S, CT5 POWERSPORT: Can you charge a lead acid battery with the Lithium mode?
    See answer

    No - CTEK recommend the correct charge mode be used at all times.

  • D250SA: Which fuse size shall I use for D250SA?
    See answer

    30 A

  • D250SA: Which battery sizes can D250SA be used with?
    See answer


  • PRO BATTERY TESTER: Can it test AGM and GEL batteries?
    See answer

    Yes, it will test AGM, GEL and flooded types of lead/acid batteries