Smart battery monitoring on your mobile phone
Power in your pocket
CTX BATTERY SENSE is a Bluetooth® enabled, smart battery management tool. It’ll help you prevent vehicle breakdowns and maximise the performance of your battery by giving you valuable, easy to understand information about the state of your battery’s charge. Just download the free app, connect the Battery Sense Monitor to your battery, follow the in-app instructions and your mobile phone will give you data 24/7, all year round. You can even sync multiple monitors to your phone for a complete battery management system. And if your battery’s charge falls to a critical level, Battery Sense will tell you when it’s time to reach for your CTEK battery charger.
Suitable for all car, motorcycle and engine starter batteries 4.5AH or over
Compatible with Android OS 4.4 and higher, iPhone iOS 7 and higher, Bluetooth® 4.0
Easy to understand smart phone application and monitor
Push notification straight to your mobile phone if your charge falls to a critical level
Can sync with multiple monitors
Frequently asked questions
Which operating systems does it work on? ×
It works on Android OS 4.4 or higher
iPhone iOS 7 or higher, installed on iPhone 4S or later models.
How should I connect Battery Sense? ×
Connect the red positive (+) cable to the battery's positive pole, and the black negative (-) cable to an earthing point on the chassis. Check the vehicle's user manual for information about what is recommended for your vehicle.
Battery Sense quick-check ×
When you add a sender for the first time:
1. Is the Bluetooth on in the phone settings
2. Are you close enough (10 meters)
3. No thick walls between the phone and the Battery Sense?
In case of repeated failure to add a sender:
4. Is there more than one Battery Sense within 10 meters?
1 – 3 as above.
4. Try to “pull-to-refresh” - what happens?
To receive notifications:
1. Are notifications turned on on the phone?
2. Are notifications turned on on the app?
3. Keep Bluetooth on.
4. Do not close the app by sweeping it off the list of recently used apps.
5. Open the app if you get the 7-day notification to reactivate background operation in case the app was shut down by the OS.
6. Ensure you are near the Battery Sense (10 meters) now and then.
Can I update manually? ×
Yes, you can update manually by using "Pull to refresh".
("Pull to refresh" = Swipe your finger downwards over the screen in list mode)
Can I connect more than one phone to Battery Sense? ×
Yes, you can connect up to 10 phones to the same sender.
How often does Battery Sense gather information from the battery? ×
Battery Sense measures the battery's voltage every five minutes and calculates the battery charge status.
Does this affect the battery management system? ×
Why is "Battery Capacity 75Ah" shown when installing the sender? ×
This is the default Battery Capacity. Click to adjust the battery capacity to fit your vehicle.
Can I place Battery Sense anywhere in the engine compartment? ×
You should place it so that it does not come into contact with moving, sharp, hot or otherwise unsuitable surfaces.
Why doesn't Battery Sense work on older phones? ×
Bluetooth Low Energy is a relatively new technology which is not available on older phones. For iOS you need an iPhone 4S or newer and iOS 7 or later. For Android you need version 4.4 (KitKat).
There are three Bluetooth classes. Which does Battery Sense belong to? ×
Battery Sense is Class 2.
Can I be notified when the battery is fully charged again (green)? ×
No, you only get notifications when the battery's status changes as it discharges, to yellow or red.
Why doesn’t the percentage show 100% when the voltage meter is higher than 12.8 V which is said to indicate a fully charged battery? ×
Measuring the voltage for estimating the charge status of a Lead Acid battery can only be done when the battery has been at rest for a certain period -sometimes more than 10 hours. This situation is likely to occur after charging the battery or after a ride with the car for instance. Battery Sence takes this into consderation when calculating the charge status.
How can I see Voltage and Temperature for my vehicle? ×
Turn on this function in the app settings.
Where can I find more information than what's shown in the manual? ×
For more information, see www.ctek.com
Can I force Battery Sense to update? ×
Yes, you can use the "Pull to refresh" function in the app, which gives you the latest measured values.
("Pull to refresh" = Swipe your finger downwards over the screen in list mode)
How close to my vehicle should I be for the app to update? ×
The effective range may be less if there is an obstruction – for example a wall – in the way.
Can I connect my phone to more than one Battery Sense? ×
Yes. The number of Battery Sense units you can connect to is only limited by your phone's memory.
What diameter are the eyelets on Battery Sense? ×
Battery Sense has M6 fork terminals, i.e. 6 mm diameter.
How do I know whether I've got Bluetooth 4.0? ×
This is not generally obvious on your phone. Check with your phone retailer.
How can I see more or less data in the graphs? ×
Double tap, scroll and/or pinch zoom in both graphs.
How big batteries does Battery Sense handle? ×
What levels do the colour indications change at? ×
The status changes from green to yellow when the battery's state of charge drops below 58%, and from yellow to red when it goes below 35%.
Can I connect my charger to Battery Sense? ×
No, you cannot. You need a CTEK accessory – for more information see
Why doesn't the panel with a figure disappear from the Battery Sense icon? ×
The panel (iPhone) shows how many senders have yellow or red status or haven't been updated in the last seven days. The panel will disappear when the app has updated and/or the state of charge has changed to green.
What does background updating involve? ×
Measurements are sent to your phone even when the app isn't active.
Why can't I find the app on App Store? I have an iPhone ×
If you have an iPhone that doesn't support iOS 7 or higher, the app won't be shown on App Store.
Why should I adjust Battery Capacity? ×
To get a more accurate calculation show as battery status.
Why can't I find the app on Google Play? I have an Android phone ×
If you have an Android phone that doesn't support OS 4.4 or higher, the app won't be shown on Google Play.
Does Battery Sense work on my tablet? ×
Battery Sense has not been developed specifically for tablets but it should work if the OS version and hardware support Bluetooth 4.0 (BLE). The app is only shown among iPhone apps, not iPad apps.
Can I connect even if I've forgotten my serial number? ×
Yes – you must disconnect the sender from the battery for at least 30 seconds and then reconnect. Follow the "lost code" guide in the app.
Why does background updating not work? ×
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.
When does the information update in the app? ×
The information is shown in the app when your phone is within 10 metres of the sender. If you have the app open in the background, it collects data every 60 minutes if you are within 10 metres of the sender.
The time scale is out of order after I disconnected Battery Sense from the battery. How can I make it work again? ×
When the Battery Sense is disconnected from the battery for a period the time scale in the diagram can be faulty or out of order after reconnect. The way to recover from this is to disconnect the Battery Sense sensor within the App and reinstall the sensor again with its identical number. You do not have to uninstall the App.
How should the negative cable be connected? ×
The black negative cable should be connected to an earthing point on the vehicle chassis (see your vehicle's user manual).
How much battery power does it use? ×
It uses about 1 mA, equivalent to about 1 Ah per month. The normal rate of discharge from a battery is about 10 mA. If the vehicle is left unused for a long period we recommend that you charge the battery.