Whilst many would think this a blessing, the Stop/Start on my SVR has been getting more intermittant for a while and now I can't remember the last time it worked. Is this a sign of a failing battery? 

Have you been using the climate control a lot recently? If you are cooling the interior to the lowest setting the load on the alternator might be enough to cause the system to lock out the Stop/Start. Mine has been doing similar (and I use stop/start all the time) for the last 10 days when the outside temperatures have been very high and I have been in town traffic. 2020 Pangea Green 1st Edition D240 New Defender 110 is here and loving it
2018 Melting Silver Mini Countryman PHEV - soon to be replaced
2015MY Corris Grey SDv6 HSE Dynamic, the best car I have ever owned, totally reliable only a cou0le of rattles in 3 years, now no longer in my care
Also in my garage is a 1996 TDi300 Defender 90 County HT made into a fake CSW

It's funny you say that I'm 3000 miles into my 2016 MY vehicle ( less than 3 months old, and after 6 weeks I have the same it now seems to work about 2 days every 3 weeks, when originally it was daily, I did think of sticking the ctek on it, and seeing if that made a difference. The lowest mileage it does is 10miles a time but generally the journeys are 40miles + on each occasion and that's twice a day minimum...

It's niggled me but not enough to complain ask yet....
I did wonder about battery, but I would hope that's not the case given such a short time, and not being used in stop start conditions much ( some days it has no need to to kick in as I just don't stop)....

It's been getting worse for a long time (many months), not just in the current weather. 

Me too! This morning it is cooler and ss seems locked out.

Also mine seems to regenerate very frequently - about every 200 miles....
Most mileage is a mixture with verey few long runs but this seems very frequent.

L494
3 SDV6

Just put the CTEK on, and it's gone straight the 80% bulk charge phase,,and stayed there for quarter of hour before heading to the 80%-100% phase, which actually I thought it would probably go straight to, will leave it on for today,,and see what tomorrow brings when it gets used, a very rare day off for it...

I have CTEKs on all of my toy cars, but wouldn't expect to need one on my daily car that does 18k miles a year! 

Indeed not, but something is potentially causing a drain to levels where it cuts out,,if it not high use of a/c cold engine etc...

But where it used to work and now isn't suggests the battery is failing or just isn't up to the job. 

My dashcam is set to switch off below 12v in park mode and appears to be shutting down all the time

I think the battery on LRs are too small - back in late 90s I had 2 batteries on my Landcruiser and wondering if this would help

I didn't have s/s on MY13 Black Edition but was never able to enjoy timed climate and TV due to battery low message even when I used ctek between uses

If I don't use DS over weekend the electric tailgate will not work Monday am due to low battery

Agree the s/s worked more in winter when ac off  Wanted a Series 2 LR since childhood but previously owned MY16 Disco Sport HSE TD4 Auto, MY13 RR Sport Black Edition TDV6 Auto, MY10 RR Sport HSE TDV6 Auto, 2007 Freelander 1 Freestyle TD4 Soft Top, 2009 Freelander 2 GS TD4 Auto, 2007 Freelander 2 GS TD4, 2004 Disco 2 Metropolis Auto, 2002 Disco 2 GS, 2000 Freelander 1 SE TD4 SW

Still hoping for a S2 one day!

When replacing your battery, put a higher capacity (amps) battery, or better make, in your car. The battery can still be the same size, or some larger ones can fit, but I find at present with this very hot weather and doing lots of local runs to the beach etc,p (even with overnight trickle charge) I'm getting warnings to turn off radio or TV/DVD soon as stationary or restart ignition. So yes with everything running, same in winter, you use more than alternator can recharge on short runs. John

RRS MY12 SDV6 HSE. Sumatra Black/Ebony & Walnut + Dynamic Pack, + Cold Climate Pack + Memory Pack, Digital TV/DVD, Premium Leather, Cornering Lights, Cooler/Fridge Box, & most Options.

That's great but we shouldnt even be talking about replacing batteries on a car that is 3 months old (mine) or I'm guessing 9-12 months old for the SVR now.

muddywheels wrote:

My dashcam is set to switch off below 12v in park mode and appears to be shutting down all the time

I think the battery on LRs are too small - back in late 90s I had 2 batteries on my Landcruiser and wondering if this would help

I didn't have s/s on MY13 Black Edition but was never able to enjoy timed climate and TV due to battery low message even when I used ctek between uses

If I don't use DS over weekend the electric tailgate will not work Monday am due to low battery

Agree the s/s worked more in winter when ac off

The start/stop has been stopped on my MY 2015 RRS more or less since I first had it. It has been back to the dealer twice now for investigation. The response is that my "driving style" is insufficient to keep the batteries fully charged! I asked what would be "sufficient" and the response was around 40 miles per day motorway (non-stop) driving or 60+ miles per day mixed urban driving to keep the batteries at full performance!!!! This prompted several questions, not least of which was the use of the plural when referring to batteries. I was told that the L494 has 2 batteries. 1 located under the spare wheel and the other on the off-side rear of the boot. Apparently, the alternator now has to keep 2 batteries fed with power but has not increased in capacity since this modification. The stop/start requires a high voltage level to maintain operation and is the first thing that gets switched off by the power management system when voltages drop. I continue to live without a functioning stop/start system as I do not generate anything like the recommended daily mileage to keep the system operable.

I don't know if this is complete BS or not as what makes a car go broom broom is a complete mystery to me, but seemed to be a plausible story. Maybe some of the mechanical marvels on the forum can comment?

Regards,

Old Jock 2018 (MY19) Jaguar F-Pace R-Sport 300PS Petrol in Caesium Blue with many bells and whistles.
2015 RRS HSE SDV6 Firenze Red with Santorini Panoramic Glass Roof, gone but not forgotten.

& following 7/8 hours on the CTEK today, the stop start now works as JLR intended.
Clearly even at 80 miles a day normal driving over 2 journeys this is not enough to keep the battery high enough.
I understood as previously mentioned that the 2nd battery was solely for the stop / start mechanism.

Must be a feature....