First time poster.

I wrote an article on my blog on how to change the auxiliary battery on the LR4. If you're interested, here is the link.
I can also paste the article here too if you want to preserve it on the forums. Cheers!



Dead Battery! 10.46V!!

 

Great post and blog! Thank you! Question for you though. I replaced my secondary battery and took her out for a drive and still no eco mode. Did you have to initialize anything or clear some code to get it to use the Eco - start/stop functionality again?

 

I had the same issue. Had a dead aux battery, replaced it and the warning went away but eco-start stop would not work. You have to reset the battery management system using an IID tool or something similar. It didn't actually work the first time, but I recently replaced the main battery as well and did another reset of the aux batttery at the same time and the eco system is now up and running. I read that you have to do install in 2x to work.

A lot of people on the forum hate the eco start stop, but I actually don't mind it. Its nice to not sit there with the car running for 5 minutes when I'm waiting to drop a kid off at school, things like that etc. Also being able to shut the system off with the touch of a button is convenient. My dad has a c7 vette and a cadillac SUV and the only way to shut off the ECO is to purchase a special 3rd party dongle that you leave in the obd port.

Service/Test > BCM-Body Control > Aux Battery Replacement

 

Thanks for the feedback. I went ahead and ordered an Autel MaxiAP AP200 Obd2 Scanne from Amazon to try and reset the BMS. I too don’t mind the eco mode for the very same reason and hope to get it up and running soon.

cheers!

 

The battery reset function is pretty specific, does the Autel have that function? I know the GAP tool does.

 

It does, along with a host of other functions. I reset the secondary BMS and it didn’t work, so I went ahead and reset the primary BMS and the secondary BMS and that did the trick. Eco mode is back and working great.

I found this video helpful and at 7:10, you can see the “Services” available… including resetting the BMS.

https://youtu.be/_KWJbwqNBUI

 

I posted this and deserted the forum In my case, it started working all by itself. The function was sporadic. I was going to replace the main battery since it was getting old and give it a try but I ended up changing the vehicle

 

Having had the battery low start engine message I decided to replace the battery ,after a run and an overnight stop the low battery messaged disappeared and my start/stop and child locks started to work again 🙄anyone else had this?

 

That is precisely some of the symptoms experienced if the battery is under capacity. These vehicles with high electrical demand require an agm battery nearly fully charged. If my “fully charged” battery reads less than 12.2 v after sitting overnight, it is replaced.
An optimal agm battery, fully charged can read as high as 13.0v
A lead-acid battery, 12.6.

Think of the vehicles alternator as a “maintainer”, not as a “charger”. Be sure the battery is in good shape and fully charged and these electrical gremlins disappear like majic.
Cheers

 

I know this is an old thread, but I was looking for info on the subject and it was useful.

I have had 2 experiences, the first on a UK Discovery 4 (2015) where I replaced the battery, and nothing changed, light on, no stop start. I was selling the car so had no time to work out the issue. In this scenario I am sure I would have needed to reset the battery data as others have stated.

The second, on an LR4 (2016) where I changed the battery (shipped from Europe as prices here are so high, it arrived in 4 days) and immediately the warning light was gone. But no stop start. That is when I came onto this thread. But I then had 2 longish runs, not city driving, a few hours apart. On the third start up, the two runs were 30 miles each, hey presto, and stop start is working again.

I am not sure I like stop start, it feels aggressive, and I honestly can imagine it is not great for any engine, but that is a feeling not factual. But that huge orange light is gone, and that I did find irritating.