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: RECOND
    See answer

    A mode that is used for reviving deeply discharged batteries, breaking down sulphation and reversing acid stratification. It requires a manual selection from the user and will add an extra step to the charge cycle, It uses a voltage of 15.8v to deliberately gas the battery in a controlled way in order to re-mix the acid to get an optimized acid balance (acid weight). This mode is also recommended for Ca/Ca batteries which require the higher voltage when charging.

  • SMARTPASS 120S: Can the starter battery and the service battery be different types of battery?
    See answer


  • Charger functions, Batteries, PRO25S: Will my PRO25S charge AGM batteries?
    See answer

    Yes, it charges all lead-acid type batteries in normal mode.

  • 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.

  • INDICATOR EYELET M8, INDICATOR PANEL 3.3M, INDICATOR EYELET M6, INDICATOR CLAMP, INDICATOR CIG PLUG, INDICATOR PANEL 1.5M: I have a INDICATOR connected to the battery all the time. Is there any risk of the battery discharging?
    See answer

    No, the purpose of the indicator is to allow you to quickly and easily see whether the battery must be charged, thereby reducing the risk of the battery being damaged because of being discharged. The INDICATOR uses about 1.5mA. Than gives 1,5 Ah /month. An average self-discharge for a battery is approx. 10 Ah/month.

  • 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.

  • 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.

  • 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.

  • D250SE: How do I activate the AGM setting?
    See answer

    The D250SE has a wiring harness with a black and a red wire, the black wire must be earthed / grounded to change the charging voltage for AGM.

  • D250SE, D250SA: How do I know if my vehicle has a smart alternator?
    See answer

    Cars manufactured 2015 and later have smart alternator. Vehicles prior to 2015 please refer to vehicle manufacturer.