OK so it’s been -XX degrees around here quite a lot of the last week. I activiated the FBH a couple of times successfully.

On the second day of doing this the car started some odd behaviour. Engine started OK but would not rev to more than 1000 and eventually cut out. Restarted quite easily. When running I was able to select all the gears but couldn’t get the car to move whilst in any of them. Still no revving at more than 1000 and engine will cut out again.

Suspected electrical problem but wondered whether the FBH running had possibly blocked something. If the battery was at fault, I didn’t think I’d be able to start the engine so easily.

Hooked up iCarsoft LR3 and had faults across at least a dozen modules.

Since there’s been ice absolutely everywhere here recently, I wasn’t in a rush to go anywhere and wired up a trickle charger which I left overnight.

After the overnight charge the car now starts as before but this time I’m able to rev fully and even drive it!

Although the charge up seems to have worked, a new battery has just arrived from Tayna which will be an installation project for me once the freezing rain goes away.

Glad I followed first instinct of battery/electrical despite the car starting up OK. What I don’t fully understand is why once the engine had started, there seemed to be insufficient oomph in the battery to allow the engine to work at full power.

BTW full marks to Tayna as usual for an outstanding delivery service to the Highlands. 2016 SDV8 AB

Without knowing the specific codes, its hard to say. A number of things are quite sensitive to low voltage - particularly auto gearboxes - which will chuck its toys out the pram, and from that other systems wont be happy, and wont want to work like they ought to.

As for once started ... it still had errors ... which dont generally clear until re-started. So it would have generated the errors on start up, reacted to try and protect the engine and remained that way until the next start where it does its error checking from scratch again. ( or once you had cleared it using the diagnostics ) V8 or else ...

Rangie just spits it's dummy out if it doesn't get a good voltage, it's not that the failing battery can't do this and that, it's more that the Rangie won't let the battery do it in case it breaks something....

If you think of how long the starter motor actually runs when you start the car you can see that it uses very little energy to start a modern car....

Someone on another forum worked out it takes around 9 seconds of the alternator running to replenish the battery after a "normal" start, I dare say it's longer than that for a Rangie but you get the idea....

Maybe someone cleverer that me can work it out for a Rangy...

Meanwhile, get that new battery in and you should be fine.... Have you tested the second battery...?? Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand Sold
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Sold
2002 L322 Vogue 4.4 V8 Epson Green (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Fisha types faster than me...!! Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand Sold
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Sold
2002 L322 Vogue 4.4 V8 Epson Green (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Checking second battery is a good shout - I will do just that. 2016 SDV8 AB

the second battery [if you have one, can also be a capacitor] is only to supplement the stop/start so i dont think its part of your problem... ... - .- -.




Y. O. L. O.
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Last edited by Phoenix on 23rd Dec 2023 11:20pm. Edited 1 time in total

9 seconds.... 20 minutes.... not too far out.....

I knew someone would know the truth....

As an aside mine has a second battery but no stop start, the main battery had dropped to around 10 volts and the engine still started fine as I guess the second battery was backing it up... Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand Sold
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Sold
2002 L322 Vogue 4.4 V8 Epson Green (Fatty Offroader) Sold
-Click for Project Fatty off roader-

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Last edited by Phoenix on 23rd Dec 2023 11:20pm. Edited 1 time in total

I would say Pete was close.  overfinch modified

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Last edited by Phoenix on 23rd Dec 2023 11:20pm. Edited 1 time in total

Fortunately, the bloke in our pub is…… Phoenix!  “If it ain’t broke, don’t fix it” -where’s the fun in that?

very true Gremlin.  overfinch modified

Much appreciate all the replies - informative and amusing all in one! At least we know where to anchor the FFRR university challenge team. Suggestions for other team members anyone?

Anyway back down to earth, I’ve replaced the starter battery (Exide EK950) which was reassuringly exactly the same size, shape and bits and pieces as the factory battery which came out. This was my first 405 battery swap, made significantly easier by watching a YouTube or two beforehand. The only c**k up was me forgetting to put the car into service mode on the incontrol app first and then getting a “your vehicle … has triggered a security alert” text from LR. Oh well, at least I know that but of security works  2016 SDV8 AB