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CTEK (40-149) CTX Battery Sense - Smart Battery Monitoring on Your Mobile Phone

  • Based on 778 reviews
Condition: New
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$67.56 Why this price?
4th of July Sale · 8% off was $73.75

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Availability: In Stock.
Fulfilled by Amazon

Arrives Monday, Jul 8
Order within 4 hours and 24 minutes
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Features

  • Fit Type: Universal Fit
  • Suitable for all 12V lead-acid starter batteries (SLI) up to 200Ah
  • The package height is 30.5 centimeters
  • The package width is 6.5 centimeters
  • The package length is 4.9 centimeters

Description

Battery sense (part 40-149) makes it possible to show you the state of charge of All your batteries in real time. Battery sense provides valuable knowledge about your batteries in a simple, user-friendly and transparent way. Knowledge of your batteries' charge level makes it easy to monitor their health status and thus maximize your battery performance and service life. Knowledge that will allow you to avoid costly battery replacements and annoying vehicle breakdowns. Battery knowledge presented directly in your pocket. Designed to fit MULTI US 3300, MULTI US 7002, US 0.8, CT5 Powersport, MUS 4.3 Polar, MUS 4.3 Test & Charge, MXS 5.0, Lithium US, CT5 Time to Go and MURS 7.0, battery chargers. Suitable for all 12V lead-acid starter batteries (SLI) up to 200Ah


Manufacturer: ‎CTEK


Brand: ‎CTEK


Model: ‎CTEK (40-149) CTX Battery Sense


Item Weight: ‎2.53 ounces


Product Dimensions: ‎11.81 x 2.76 x 5.91 inches


Country of Origin: ‎China


Item model number: ‎40-149


Batteries: ‎1 Unknown batteries required.


Is Discontinued By Manufacturer: ‎No


Exterior: ‎Machined


Manufacturer Part Number: ‎40-149


OEM Part Number: ‎40-149


Voltage: ‎12 Volts


Date First Available: December 4, 2015


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Jul 8

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Lost Connection? Not Updating? Not Responding? Here's My Fix!
I own 2 CTEK Battery Sensors both in the same car just to be able to monitor my high-end car stereo system. One for the main engine battery & the 2nd one to monitor my Shuriken auxiliary battery installed in the trunk which powers my car stereo system. I have read the complaints and I have experienced many of the same problems as you all have. When it's working it's great when it's not, kind of sucks. So after experimenting with different options & company recommended fixes, what I found out was when your phone gets an automatic update or another app gets an update it may cause your Battery Sense to lose connection. What I did was just restart my phone within the Bluetooth range. After the restart, go to your Bluetooth settings on your phone turn off Bluetooth and then turn it on again. It should resync & update with the present time. If it gets jammed up again, repeat the process. The same goes for when you switch out or replace your battery. Here I thought just closing & then reopening the app would allow it to update, how wrong I was. I hope this helps. ... show more
Reviewed in the United States 🇺🇸 on July 30, 2020 by JJreal

  • Great battery monitor for Multiple Vehicles
I’m fan of CTEK chargers and been using it for like 6 some years. I finally got two of this monitor after I order one first. I read kinda funky on setup and also how app works . I have kinda agree but adding 2 second unit it gave me little grief but I have both installed for awhile and never have issues Sometimes when you check one vehicle it may have an issues but usually close the app and access the 2nd vehicle works fine. There is a time no issues accessing both . App is pretty simple and definitely Bluetooth isn’t going reach far out in your house but easily read the data by the vehicle. You can expand the graph in app as well. So you can see in detail if you need it . Also while you are driving you can get good reading . ... show more
Reviewed in the United States 🇺🇸 on March 4, 2022 by LIberator

  • This product is great and the manufacturer CTEK is very responsive to email ...
This product is great and the manufacturer CTEK is very responsive to email questions. I work from home and the result is that my cars not driven for long distances much, usually short trips of 5 or 10mins for going to the gym or out to eat. This is bad for the car's battery and I bought this battery sense, along with the CTEK MUS 4.3 charger to make sure the charge level of my car batteries do not get to too low a level. A few things that you should know: 1. In most US vehicles, the nut size for the battery post is 6mm. 6mm nuts are also listed as "M6" in places like Lowes. You will want to buy a couple of these 6mm nuts so that you can secure the positive and negative terminals of the Battery Sense to the battery without having to remove the exiting nuts on the battery posts. With the extra 6mm nuts, you can simply thread them over the extra length of the screw and "sandwich" the Battery Sense terminals to the post. 2. The CTEK battery post does show voltage and temperature. They are not on by default however, you need to go into Settings and turn on those displays. They are shown when you tap on the battery and displays the details. One small quirk: When you install the App, it ask for the device ID, which is part of the alphanumeric displayed on the device itself. If you try to entire the entire ID shown on the label of the device, it won't work. You'll have to enter only part of it. Why would they do something like this is beyond me. ... show more
Reviewed in the United States 🇺🇸 on February 23, 2017 by Kindle Customer

  • The device itself is pretty easy to use
The device itself is pretty easy to use. Connected to the car battery fine. Bluetooth connects fine to my Samsung S7. The accompanying phone app is very poor though. It often has a hard time connecting. It crashes frequently. It has screens that don't update sometimes. The readings on the graph are sometimes questionable and confusing. The chart shows a scale up to 100% (rather than actual voltage reading) and is often off the top of the graph so you can't see the measurements. After a complete battery recharge (or disconnecting the device) it seems confused and takes 24 hours or so to settle on what the readings really are. During that time I see a steep drop until the voltage readings seem to settle in. After that it looks accurate. It takes a reading every 5 minutes and the ups and downs correlate to the times the car is driven. We think we have a parasitic draw on our min-van and according to the graph the voltage drops about 0.1V between 2am and 7am every night. After a couple weeks the battery is dead (which prompted us to purchase this monitor). This matches up with my manual multimeter measurements. It works pretty well if you give it a day or two to get used to your battery. I wish the app was better and that you could see and export actual voltage measurements. ... show more
Reviewed in the United States 🇺🇸 on January 20, 2017 by Jake Roberts

  • Monitor system
This is a great idea but doesn’t always connect. The range stinks and is glitchy.
Reviewed in the United States 🇺🇸 on April 19, 2022 by Neil Rowland

  • Peace of mind with this device.
I recently stored one of my cars long term. I wanted an easy way to check the status of the battery so I can share my battery charger between multiple vehicles and multiple smaller batteries for lawn care and other uses. After took about a month before I got a note to recharge. I think the best way to use this device is to connect it, perform a full charge with a smart charger (like a CTEK), and then let it rest. It likely need a fully charged baseline to start with. I’m happy with it. I’m almost considering more for other vehicles that do get driven more often, but not often enough, just to make sure everything is going well with the batteries. ... show more
Reviewed in the United States 🇺🇸 on February 28, 2021 by E.

  • Low Bluetooth range
If you get in your car every day this will work, since your phone will be close to the battery for many minutes. But if you don’t drive frequently and only walk past your car occasionally, you will never get a current reading.
Reviewed in the United States 🇺🇸 on November 22, 2021 by Don Pattee

  • it works
I installed on one my truck and camper trailer batteries. now no need to open the truck hood or remove battery covers to check battery voltage when dry camping. no going out in the cold, the rain or any reason. easy to keep track of charge level.
Reviewed in the United States 🇺🇸 on March 10, 2022 by jimeb

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