I have the low battery start engine warning.

When running I am getting 14.8 on the posts on in the engine bay.

When switch off sons drops to 12.2, when checked at battery main is 12.3 and backup 13.2.

The date on the battery post is 26 15, which I assume is the manufacturing date, it is a landrover battery.

If so time for a new one

Hi John,

Given that FFRR’s eat batteries for breakfast, your 8y.o. battery is probably well past its prime.
Is your tailgate not sluggish?
Google “Kingbolen BM580” and just get one, eBay/Amazon/AliExpress (latter is cheapest £15).
Tayna are probs the leading UK suppliers, very fast service & good prices. You need at least an 850CCA AGM battery.
I had similar issues last year, the above device showed it was down to 29% of original capacity, but still starting the car in Summer, but I didn’t wait for Winter to arrive!
Do you have a CTEK MXS 5 or similar to leave hooked up?  “If it ain’t broke, don’t fix it” -where’s the fun in that?

Remember a lot of L405's have a second battery - they will both need testing in isolation to determine the guilty (or more guilty) party...

I do have the ring version of the CTEX charger, been useful on the L322.

I did disconnect and the main battery read lower than the backup battery. The top tailgate is sluggish you what to give it a helping hand

The monitors do seem a good idea.

Looks like the card will be used again

The l450 I'm thinking of buying had the battery low warning sign on today as well - it also was a note on the recent service. What sort of £ am I looking at for a replacement battery please on a 2014 3.0 TDV6 L405? Thanks

It depends which battery.... Aux. battery cost me £135.50 delivered (70Ah, autostop rated Bosch S5A08) Starter battery 020 (should be 019) Bosch autostop rated S5A15 105Ah / 950CCA cost me £182. Both above the specified batteries rating but to me, it was worth the cost for reliability and knowing there is a 'bit extra in the box' before a booster pack is needed.

Google Tayna batteries, search on there for 850CCA AGM batteries.  “If it ain’t broke, don’t fix it” -where’s the fun in that?

I found these to be as reliable and value for money as Tayna https://batterygroup.co.uk/

This one has a 5-yr guarantee:

https://www.tayna.co.uk/car-batteries/enduroline/019-agm/

Suitable for L405 TDV6.

I bought this last year, good to have the 5 year guarantee, given the propensity for FFRRs to eat batteries every few years….. “If it ain’t broke, don’t fix it” -where’s the fun in that?

I’ve used this one for years, free next day delivery, good range to choose from.
batterymegastore.co.uk They also trade as BMS Technologies. 2013 SDV8 4.4 SE Luxor.
1960 Series 2 88 inch diesel.
1955 Series 1 86 inch petrol.

My 405 is a high days and holiday car and when I went to use it I always got the low battery warning. This was accompanied by the tailgate not working and the auto stop start not working as well.

I tried my CTEK conditioner and next day hey presto, all is now well. What I have also discovered is not locking the car when it’s in its locked garage saves the battery as well.

Anyway, 8+ years on and it’s the same battery still going strong.

I agree, never lock my car in the garage. The alarm and immobiliser are draining current. Like the previous post, mine can spend a couple of weeks in the garage. 2013 SDV8 4.4 SE Luxor.
1960 Series 2 88 inch diesel.
1955 Series 1 86 inch petrol.

Just to add in my own battery experience.

My car would never operate stop/start and I found out the interior lights wouldn't light either after they did once the main battery was renewed. The stop/start feature also works on the new battery. So there are plenty of warning signs that the battery isn't as fresh as it could be ahead of being advised it is struggling. I tried charging the main battery and it wouldn't accept a full charge, another sign that after 6 years it was tired.

The ancillary battery though, also 6 years old is fine. Higher (normal) standing voltage and accepted a full charge.

I got my replacement battery from Halfords (a Halfords battery), fitted which on my trade card was the same price as having Tanya deliver.

I am looking forward to a knackered battery as it will save me switching off the stop ,start.  overfinch modified

I'm lucky, second battery and no stop start....

Can't you pull a fuse or something...!! Pete

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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-