Assuming battery is good, how long should you be able to leave without use and being ok to start? 2009 Range Rover Vogue 3.6TDV8, Bournville, Parchment/Navy
2005 Jaguar XJ350 3.0 V6 Sovereign, Jaguar Racing Green, Ivory
1997 TVR Chimaera 450, Formula Red, Grey

mine had a scary "gearbox fault" flash up on the dash this morning as it started before immediately clearing - I'm hoping that was low voltage too. The FBH hasn't been doing owt recently and it's felt a little slow to crank on the colder days so Halfrauds are installing a replacement battery on Friday (too cold to stand out there and fiddle with it myself and others seem to have had luck with them recently). 2012 RR Westminster TDV8
2008 Audi S5 4.2 V8
2006 Mazda MX-5 R/C Sport 2.0

Gone...
2007 RR Vogue SE 3.6 TDV8
2005 Ford Focus LX tdci 90
2006 Mazda RX-8
1996 Land Rover Discovery 300tdi
1998 BMW 523i
...

If the full fats are anything like the discos as soon as the battery gets low you get gearbox faults etc flashing up and then instantly clearing when if first happened to me I almost myself but I got the battery tested and replaced these cars eat batteries with all there electronics heats seats wheels etc 2012 Range Rover Westminster 4.4 TDV8
2006 Discovery 3 HSE 260k miles and still going strong with a new owner

dhallworth wrote:

This is the adapter we use:

https://fnltd.co.uk/shop/tow-electrics-cha...c-p45.html

This is the charger we use:

https://www.halfords.com/motoring/battery-...80326.html

They are smart chargers that don't try and charge the batteries all the time. They will monitor the battery and top it up as and when required. Ours sits connected all the time and only comes off it when we use the car. I can't imagine there's many FF's still on the original battery and not having issues so it must be working.

David.

Possibly a red herring/ coincidence but this only takes a couple of minutes to check and is free!!
I’ve had a few recent issues with my 2011 TDV8, the latest was the starter motor “click” problem so I fitted a new starter, a few days later it decided that it wouldn’t start at all, arranged for a tow home then found the manual P release lever (under the cup holders), turned the ignition on to tow it home and it started. Ran fine for a couple of days then failed to start again. Intermittent faults!! I wasn’t convinced that 2 starters were faulty so I wired a bodge to the solenoid trigger and used it until it failed again-used my bodge and the starter was fine so the fault was with the car not the starter.
That was the final straw I’ve recently done all of the brakes including pipes, new dampers on all 4 corners, O2 sensors and all normal service stuff. It’s 10 years old, I’ve had it for 5 and it’s done over 100K now so I’ve got no complaints about fixing things but once it isn’t reliable it’s no good to me.
So number plate, winter tyres and dashcam off ready for a trip to WBAC.
I remembered that I dropped the cover from under the cup holders when I was looking for the P release so decided to fish it out and fit it properly. While I was in there I noticed that the P release lever has a slot in it to lock it in place, I had to wriggle it about to get it to lock THIS HAD NEVER BEEN LOCKED BEFORE.
I hope I don’t regret posting this - the car has operated perfectly since. Previously there would be odd random messages about gearbox or parking brake fault, these would be months apart and I would assume this was just normal Rangerover behaviour.
I’m the only person who has worked on this for almost 5 years which is why I suspect it has been like this since it was new.
I’m now planning on keeping it again if it continues to behave.
If you are have problems like this it’s worth a look, it literally takes 2 minutes.

thanks for taking the effort/time to type all that text out @cass, but I've now read it all multiple times and haven't got a clue what you're actually advocating trying or what fixed a problem for you !

Short version, it’s worth checking the gearbox P position manual release lever is correctly locked if you have starter problems.