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

  • 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.

  • Charger functions: Are there CTEK chargers for other battery types?
    See answer

    CTEK also produces the CTEK LITHIUM XS charger, which has an ideal charging programme for 4x LiFePO4 (lithium iron phosphate) with a nominal 12V terminal voltage.
    The CTEK LITHIUM XS can also communicate with the battery's built-in electronics if the electronics have shut down the battery to protect it against deep discharging.

  • 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.

  • 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.

  • CONNECT CIG PLUG: Can I use your CONNECT CIG PLUG to charge the battery through the cigarette socket in my car?
    See answer

    Yes, but you should check that you have voltage to the socket even if the vehicle is switched off. If, for example, you can charge a mobile phone or get a GPS to work when the car ignition is switched off, you can also charge the car battery this way.

  • General: A CTEK charger is so small. How can it charge so quickly and efficiently, when compared with ordinary chargers?
    See answer

    CTEK's chargers use the same type of technology that computers use to reduce dimensions, to increase power and to charge using a well controlled and 'pure' current. Also, think how big mobile telephones were 15 years ago and how small they are today, and can even so do so much more.

  • Installation: Can I connect all of my 12V batteries and maintenance charge them all at the same time?
    See answer

    That is possible. But remember that all batteries should be fully charged individually before they are connected in parallel. Bear in mind that the combined size of the batteries must not exceed the recommended charging range of the charger. If the batteries differ greatly in size (Ah), age and condition, this could cause great wear to the batteries that are in the best condition. A battery in good condition that is being stored for the winter might self-discharge under 90% of fully charged once or twice over the course of the winter. But, batteries in poor condition may do this once or twice a week. If the batteries are parallel connected with a charger connected, each individual battery does not get the charge it needs. It may be easier to set a INDICATOR on all individual batteries and move a charger between the batteries needing charging. This gives each battery the best charging based on its individual needs and no battery will become worn and require early replacement.

  • General: Can I leave the charger connected to the battery for a long time?
    See answer

    Yes! CTEK chargers are developed to fully charge a battery and then automatically switch over to long term maintenance.
    Before leaving the charger unattended for long time, ensure that the battery is fully charged, indicated by a green light.

  • 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

  • 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.