I'm guessing a bad battery. If something was off with the BCM, the battery would have been fully drained within 3-4 days.

 

It's what I guess Also. The battery is 4 to 5 years old... Original one.

 

Battery changed... Works better ^^

I had to remove the spare wheel support to access battery bolts... It was awfull... but once done, everything is going well

 

and finally...not >< I got AGAIN this awful message
the battery is new, I used a Ctek tecnder, also added an extender with battery level meter... and within 4 days the meter indicates the battery condition came from green to red
this become to make me crazy
I will never be mind peacfull when I take the car and let it for a while somewhere

 

You obviously have a battery drain, heaps of threads and posts around here about that problem.
Problem is it could be any one or more of dozens of different things causing the drain so not at all easy to find.
You need to take the car to a good mechanic or an auto electrician to diagnose and find out what exactly is causing the drain, then with any luck it will be an easy fix.
It would also be good if you could take the car to someone who has this nifty gadget: https://www.jaguarforums.com/forum/f...9/#post2369480

 

Hi
very interesting device. I'm jumping in this hread

 

Pls excuse my ignorance...2017 V6S CONVERTIBLE Battery Disconnect/reboot switch.....MY GROUND CABLE SEEMS TO GO UNDER AND TO THE STARBOARD SIDE UNDERNEATH THE VEGITARIAN STYLE TRUNK COVER...NOT TO THE TRUNK FLPOOR. How do I access the Ground Bolt at body??
I am a dumb cowboy, Sir

 

Take the floor cover off then lift the box out and it should be under there.
Of course you have a 'vert and I have a coupe so I may have no idea what I am talking about!

 

Thank you Mr Oz....I appreciate your assistance and knowledge concerning Jaguar F Type! I had removed the "box" only to find that the designated placement of ground bolt was a hole covered with Jaguar white factory assembly tape. Apparently on this 2017 V6S Vert.....the ground cable comes off the battery top directly Starboard (straight right) and under the upper "shelf" of trunk liner!! I could not trace further as I broke a plastic panel button in the process....has anyone with a 17 convertible done this install??
Thanks , Spark

 

While on the subject of a possible new battery for the F-Type, I checked a link I have to one of the very few Oz sellers of a suitable AGM battery.
It seems the price has risen just a tad in the last three months!
https://www.ebay.com.au/itm/car-batt...QAAOSw28Bc1Ru6

 

For $4k AUD, it better be very nice. Perhaps it uses Scotch instead of sulfuric acid...

 

A bit expensive, but on the plus side it has a full 2-year warranty. Gee, I wonder if this $4000AUD battery would work in Canada? All I could get for my F-Type here was a $300 AGM with a 4-year warranty.

 

Yeah, these Aussies will complain about everything!

 

WTF? 4000 AUD for an AGM battery? Gold plates instead of lead?

 

And it's $4429, not just $4,000.
The seller must think there is a sucker born every day, makes my $159 special look even better now.

 

I found that getting an OBD2 Bi Directional code reader and resetting the Battery Management System solved all my battery woes. For some reason, the computer leaves some systems operational 24/7 if it doesn't get reset when the battery gets replaced or if an ODB2 device is disconnected in some sort of way. I'm confident that I can let the car sit for weeks without any worry of a dead battery now. I've stopped using a battery tender and all the other remedies so many folks have suggested.

 

We occasionally travel away for 3 weeks at a time; in addition I was not mobile (new knee) for a few weeks so I started getting the message recently. I've never locked my car in my garage. Day before yesterday I disconnected the battery for 30 seconds. That seemed to solve it.

Yesterday I went to calibrate the windows, in my garage, engine not running but systems on. After several tries on both sides - no luck. After I gave up - the magical message came up again - Battery Low - please start engine.

I opened my hood and hooked up my trickle charger. This morning it read (on the charger) full charge. I again disconnected the battery for about 30 seconds and reconnected. I chose to wait until driving the car again to try and calibrate the windows.

On a related note, I choose to simply disconnect the positive lead because it's readily accessible vs. the negative lead. I realize many have instructed conventional practice of disconnecting the negative lead but the car doesn't know the difference of which lead you disconnect. For less practiced wrench turners, the instruction to disconnect the negative lead comes from years of working with many different vehicles where there are likely bolts/body parts/metal (all grounded) within the wrench's distance from the lead. If you accidently touch a wrench that you're touching to the negative lead to any of that metal - no issue - it's at the same voltage potential. if, however you touch the positive lead through a wrench to ground - big issues. Hence the conventional wisdom. Since the positive lead in my car is surrounded by plastic - no worries. ALWAYS be cautious when put a wrench to a positive start battery lead (when the negative terminal is also connected to the battery), however with a touch of common sense and caution there's no issue in disconnecting the positive lead in this car.

In any case, once I started out today for an errand, while in my neighborhood driving down the road I programmed both windows using the same methods as in my garage. They both worked perfectly the first attempt. The battery low message did not re-appear.

So... thought I'd share these thoughts with y'all. I could NOT reprogram my windows with just the 'key on' (i.e. systems turned on with engine off). Perhaps that's because my battery was not at optimal level, but certainly driving it worked fine. And for those of you who don't want to contort yourself in an effort to disconnect the negative lead from the battery or the body (or drill a hole in your trunk) - simply (with some simple awareness) disconnect the positive lead while obviously not using a long enough wrench to touch some ground somewhere (where I don't know!).

Last but not least - some of you with more wisdom than I have posted that with the doors unlocked, there's a much greater drain on the battery than if the doors are locked. I think I've also inferred in a post that 'double locking' might even reduce that drain more. Can anyone affirm this as reality vs. urban legend?

 

Hooking up a battery maintainer (CTEK or NOCO) (not a trickle charger which could overcharge the battery with prolonged use) and using it regularly is the best practice. No amount of regular driving keeps the battery fully charged. It keeps it charged enough to operate the vehicle frequently but not enough to drive it a couple times for one week and then let it sit three weeks. Eventually the battery will be drained low enough to give the message. Doesn’t matter whether you’ve locked or double locked the car.

 

Yes, there IS a difference between a trickle charger and a Ctek

Here's their site, and THEY do refer to them as 'chargers', but the MXS-5, which many on this forum use, also will do a conditioning step. The MXS-5 has option for motorcycle or car battery, and lead-acid or AGM.

https://www.ctek.com/charging-soluti...ttery-chargers

Our 2018 corvette coupe came with a Ctek model that plugs into a port in the rear trunk.
I bought an MXS-5 for my 2017 F. While I drive it almost year 'round, there are several instances, like right now in Central Wisconsin that it stays in the garage. ... snowed, snow melted, slop on roads, rained/misted for a couple of days, etc. It goes on the Ctek. I used the Eyelets on the Pos battery post and on floor neg ground post to make it more permanent than just using the clips. I also have a 69 E type that I have a CTek for, all the same reasons, though he gets cleaned and stored in his cocoon over our winters. The CTek is then just attached via the clips to that battery.
I'm sure you've read the other battery-related posts that emphasize that these cars are VERY sensitive electrically. They don't like having any less than the voltage they were promised. The Fs put out weird codes and messages when the batteries get older (and perhaps weaker). There are some owners here who will report that the AGM batteries lasted 10 years... the usual is 4-5. You can also check to make sure the car has gone to sleep (after being parked and shut off) when the emergency/hazard flasher triangle is no longer lit. I lock my garage, but don't lock the car and the triangle still goes out after about 15 minutes.

 

I park my car in my garage, unlocked. I got back from a 3 week vacation and the battery had no issues.

I don't believe 'double locking' is a thing in the U.S. I'm sure there is some sort of obscure rule prohibiting it, maybe to keep you from locking kids in the car or something. Either way, I often see battery maintainers being used to address a symptom. Having said that, they can prolong the length of a battery, but I only run them on motorcycles.