2020 Defender HSE.
I have had a warning about the battery being low and charging system errors for a while now. Tonight the computer went crazy with faults. Suspension error, charging error, finally gear box error so I pulled over and got a tow to the dealer.

Even my dash cam has been restating to "save battery of the car"

Whats going on?

 

Sorry. To be mean. Please do a search and you will learn everything you need to know.

 

I would agree, most of the answers can be had by doing a quick search.

That being said, I had the low battery message for the first week of ownership even though I drove to the office and back every day; round trip was 26 miles. It took a day on the charger at the dealership to get it resolved. I first noticed it when trying to do do remote start.

No issues since then, but we also drove 1600 miles to and from the Black Hills of SD last weekend for a small trip. Should be fully charged now!

Rob

 

I did a search for battery and charging and did not see anything related. Do you see a thread on this topic?

 

Mark M: This one might help a bit.

https://landroverforums.com/forum/ne...estion-104102/

Our new generation JLRs use AGM batteries -- two of which I but in my boat by a forgetful mistake recently and very quickly destroyed them by using a lead acid battery charger. Foolish me.

So, the electricity no longer flows straight from the alternator to a battery via a simple voltage regulator. Instead, the AGM is fed by a logic based electronic brain, with software monitoring power consumption, battery temperature, etc. Do not assume the software within the car casts warnings for all potential current flow and voltage issues.

Too many possible current failures to trip a warning code.......

 

You may also find the attached file educational .....

 

My 2020 HSE gave a few low battery warnings during the first few weeks of ownership. The area I live in has extremely cold winters so the dealer installed a DEFA battery charger and engine heater. I plug it in occasionally during weeks with only short commutes and the warning has not popped up since. Subsequently, you can also use the warning as an excuse to drive your Defender more.

 

Will a battery tender plugged in the rear 12V outlet be okay?

 

My non-expert read of the "Battery and VQM" Pdf (assuming the Defender elec. system is similar to the D5 one) suggests that a TRICKLE Charge (ONLY) of current you attempt to send to the battery from the rear 12V outlet with the vehicle shut down will NOT reach the battery due to relays and diodes not enabling such a flow circuit to occur. If you attempt to flow current from the rear 12V with the vehicle on --- well, that I think just would not be wise to contemplate.

You can check this the next time you find you have a low voltage situation and the vehicle shut down by trying to TRICKLE charge ONLY from the 12V outlet and monitoring the amperes flowing out of the charger (assuming it has this feature) or by seeing if the low voltage warning goes away after several hours or by measuring the voltage at the battery or at the front charging posts after several hours.

Better and easier and SAFER and MORE GUARANTEED than all that, just connect to the front two charging posts, under the hood, where we know the current will flow when the Vehicle's Battery Monitoring Systems determines power is needed from your AGM battery charger with either the engine on or off. (Make sure the charger is suitable for AGM batteries.) PowerfulUKLTD. com has a video on how to do this.

And under no condition connect directly to the Negative terminal of the battery, as this circumvents the Battery Monitoring System and may expose the vehicle's battery, current controls, and software & hardware to inappropriate voltages.

 

It's a Land Rover Ctek battery tender.