My charger gets very warm – is this normal?
Yes, this is normal when the charger is working hard to charge your battery (steps 3 & 4). The Ah size of the 12V battery, it’s age, condition and amount it is discharged are all factors.
My charger never reaches pulse maintenance – why?
The charger stays in float maintenance mode for 10 days, keeping the battery topped off using the minimum level of current. After 10 days, the program moves on to the last stage – pulse maintenance – for long term maintenance.
Why is half-battery lamp flashing rapidly and the full-battery lamp is solid on my MUS 3300 charger?
Most likely a bad connection to the battery. Move the clamps or cig plug accessory and make sure there is no loose connection in the quick connector. The charger could also be working in the desulphation phase.
Can I charge the battery without removing it from the vehicle, or opening the caps?
There is no reason to disconnect or remove the battery from the vehicle – or open the battery caps – while charging. CTEK chargers are spark proof, reverse polarity protected and electronically safe.
Can you connect a CTEK charger directly to the battery or does the negative connection need to go to the vehicle chassis?
When using a CTEK charger, you can use both connections. The charger should be connected according to the vehicle user manual. If there are no other recommendations in the vehicle manual, the negative or black connector should be safely connected to the chassis.
If your vehicle has a BMS you cannot connect to the negative battery pole, the connection must be made to the earth or ground point, if you are in any doubt then connect to the nearest earth or ground point. Eyelets can be permanently connected to the battery as the charger is not usually attached to the eyelet cable when the cable is being connected, so there is no risk. The eyelet connections also give you enough time to check the correct attachment points.
Also, if the battery is disconnected or removed from the vehicle then both connections can be made directly to the battery terminal.
What charger is suitable for my vehicle?
Choosing the right charger can be determined by the Ah size of your battery. The more amps the charger can deliver, the larger the battery capacity it will charge. The website will give ideal battery size range for each charger in their technical specification or use our Charger Selection Chart for recommendations.
Can I charge my vehicle through the 12 V (cig) socket with one of the CTEK cig-plug accessories?
Yes, if your socket is still live when the ignition is turned off. Check the vehicle user manual, contact your vehicle retailer or test it with any other cig-plug device that works with your vehicle with the ignition ”off”.
Can I charge more than one battery at a time with my 12V CTEK charger?
Yes, as long as your 12V batteries are connected in parallel and that your battery bank is within the recommended Ah capacity range of your particular CTEK charger. (example: our MXS 5.0 charger is recommended for maintaining a battery or bank of batteries up to 160Ah in capacity).
Be sure that the correct procedure for charging in parallel is followed and that your battery bank is within the recommended Ah capacity range of your particular CTEK charger.
Why is my MUS 7002 charger “clicking” while charging?
The relay noise in your MUS 7002 is not unusual and may become more apparent with age or in colder weather. It may also be more noticeable on batteries that are beginning to fail. If it is still providing correct voltage and the indicators show correctly, it is working properly.