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. For fastest response please write to us in English.

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Top 10 FAQ

  • Charger settings: AGM / * Snowflake
    See answer

    Because the AGM battery has a low internal resistance it can accept a higher charge voltage, in this mode the Bulk charge rate is 14.7v which is the optimum chare rate for the AGM type battery. In cold weather the internal battery chemistry slows considerably, this leads to the battery being reluctant to accept charge at a normal rate. By raising the charge rate to 14.7 (15v on the Polar) the battery accepts charge more readily

  • CTX BATTERY SENSE: Battery Sense Software update
    See answer

    12th July Issues have been reported with the latest update on our Battery sense app – our developers are currently working hard to rectify the issue. In the mean time we have taken the decision to roll back to the previous version of the app, We have been assured this will happen over the next few days - iOS first then Android to follow.

  • Batteries: EFB or ECM
    See answer

    EFB stands for Enhanced Flooded Battery, ECM stands for enhanced charge mat, two different names for exactly the same type of battery and both are similar in set up to a standard Flooded battery. There are some design changes with this technology, active plate material is more dense, anti corrosion treatment for negative and positive grid and lower specific gravity to improve charge acceptance are just some of the differences.The EFB battery provides a more cost effective battery solution over more expensive AGM type batteries.

  • MXS 5.0 CHECK, XS 0.8, MXS 5.0, MXS 5.0 POLAR, MXS 10EC, MXS 10, MXS 5.0 TEST&CHARGE: is lit
    See answer

    Explanation 1: Reverse polarity.
    Test: Make sure that the + cable/clamp is connected to the + terminal and the – cable/clamp is connected to the – terminal.

    Explanation 2: Loads are connected to the battery which requires more power than the charger can provide.
    Test: Turn off or disconnect the loads when charging.

    Explanation 3: The charger is not connected to a 12V battery.
    Test: Test with a fresh 12V battery.

    Explanation 4: The charge cycle is interrupted in step 1.
    Test: Test to restart the charge cycle, if it still fails in step 1 the battery is sulphated and needs to be replaced.

    Explanation 5: The charge cycle is interrupted in step 4.
    Test: Test to restart the charge cycle, if it still fails in step 4 the battery is can’t be charged and needs to be replaced.

  • Charger functions, MXS 5.0 TEST&CHARGE: I have a CTEK charger. It used to work well, but now nothing happens when I press the mode button. I can't change between the "MC", "CAR” and "SNOWFLAKE” modes. What can I do?
    See answer

    If you can't change the charging mode by pressing the mode button regardless of which battery you are trying to charge, the charger is probably faulty. If you still have the warranty, I recommend you go to your dealer with the charger, the receipt and a completed warranty claim form.

  • Batteries: AGM
    See answer

    AGM stands for Absorbed Glass Mat and differs from a standard Flooded battery in that the electrolite is held on a glass mat and pressed against the active plate area, instead of being allowed to flood around the plates. This type of battery has a low internal resistance and can accept charge very quickly making it ideal for the modern start stop systems. If the battery casing should become damaged the electrolite will not leak out.

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

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

  • MXS 25, M25, PRO25S, PRO25SE, MXT 14, MXS 7000, PRO15S, M100, M300, MXS 25EC, M200, M15, MXS 7.0: is lit and then turns into error mode
    See answer

    The analysis phase is testing if the battery can retain the charger given.

    Explanation 1: Large loads are connected to the battery and are draining the voltage.
    Test: Disconnect the battery and try charging again.

    Explanation 2: The battery cannot retain the charge given.
    Test: The battery needs replacing.

  • Installation: CTEK manual says: ”Connect the black clamp to the vehicle chassis remote from the fuel pipe and the battery" . In the picture beside is shown, that the black clamp is connected to the battery's negative pole. What is right?
    See answer

    The text describes how to connect to a battery in a vehicle. The picture shows how to connect to a battery not connected to a vehicle.
    The charger should be connected according to the vehicle user manual.

  • Installation: Why do you connect minus to ground and not to the battery?
    See answer

    You can connect a CTEK charger directly to the minus pole instead of to the chassis without any risk. CTEK recommends connecting the minus clamp to ground instead of the minus pole to eliminate the risk of sparking close to the battery. Explosive oxy-hydrogen gas could be found near the battery. However, CTEK chargers are non-sparking and with their smart charging, generate minimal oxy-hydrogen gas. There is therefore very little risk associated with connecting both clamps to the battery poles.