Having just replaced my battery, I have read here from previous posters about doing a battery reset after replacement. I do not own the GAP tool but just purchased a Foxwell NT710 which I use for my Porsche Boxster, and I am still in the learning stages. I can purchase the software for the Defender, and in the Support/Applicabilty section it lists the modules it can make changes to. There is a module listed as BECM, or ‘Battery Energy Control Module. This may be trying to compare apples to oranges, but in the GAP tool is there a similarly named module that is what is used to perform the battery reset after replacement? When doing a battery reset using the GAP tool, what steps do the GAP tool users follow to complete this task?

 

I ran the Gap battery replacement routine (Service Test - Gateway Module). See screesnhot below. I did a complete write up in this thread.

 

Is this really necessary?
I replaced the battery in my girlfriend’s Defender and all seems normal.

 

I’m not sure it’s necessary, that’s why I posted my inquiry. If you read my related post about battery replacement and the failure of my Remote Climate feature after replacement, which I have used regularly over four years, and another poster’s suggestion that the module controlling the battery may be remembering the low voltage state and not allowing my Remote Climate feature to operate, it becomes a bit clearer. My battery may need a reset to tell the module that there is a new battery installed. Certainly, a simple battery swap may be possible, and my DIY replacement threw no codes or error messages, but the fact remains that my Remote Climate feature suddenly stopped working, so the prudent thing to do when troubleshooting is to look back at what was the most recent change, or action taken just before any failure. So that is exactly what I am doing.
The only other possibility is a suspect DC to DC converter which could also be the culprit, since it activates an electric pre-warmer which may be part of the problem if the battery memory precludes it from operating. Hence the POSSIBLE need for a battery reset. Have you read about the DC to DC converter issue? Or the many posters here who own the GAP tool and have performed a battery reset after replacement? If you delve deeper into these previous posts you will get an understanding of the underlying intricacies of the electronics that control our Defenders. But I’m glad the replacement of your girlfriend’s battery did not lead to any of these issues. No two vehicles share the same issues.

 

I ran the Gap routine as the workshop manual shows this:


Whether that's just good practice or necessary, I don't know.

 

I’m with you on that. One camp says it’s necessary, while others have claimed they have replaced their battery with no repercussions. My service advisor claims it needs to be done after replacement, of course that’s what they are instructed to say, but these advanced vehicles become more quirky with each iteration, so who knows anymore.

 

I've had the BMS control module unplugged from the battery terminal since Dec '21 to keep the auto stop/start from happening. Still on original battery and I guess I won't be resetting anything when the time comes to replace it.

 

I cannot vouch for Defender, but on my Range Rover I replaced the battery and thought I would test the notion that the BMS will over time figure itself out.
I can safely say that it does not, at least not in month or 1000 km.
I still maintain that it is the dumbest of dumb systems I have come across. How it is possible to determine that battery is on the way out and start disabling for example stop/start, yet it cannot figure out that a new battery is installed and thus not reset? Even TPMS have more intelligence than this.

 

Exactly. Even something as simple as changing the battery requires a trip to the dealer ($$$), or a GAP tool. Pretty soon they’ll be using an electronic coded drain plug so we won’t even be able to change our own oil.

 

Most modern cars nowadays force battery replacements to be coded to the vehicle. I guess it is one way for them to make more money. It is annoying that you have to go to the dealer to have a battery replaced.