Jumped in the car, pressed start, very brief flash of a message about abs or traction control not working (split second so difficult to be sure), then it all shut down. Never got to the stage where the gear knob rose. Tried getting out, locking and unlocking. Same issue. Looks like I’m stranded at home tonight.

Thoughts? 2025 P550e AB

Ours did something similar when the battery got really low on it. Assumed the messages were down to the low voltage. So maybe check the battery voltage? MY17 Santorini Black L494 Autobiography 5.0 SC - Sorry!
Previously Bell a 2015 MY16 Loire Blue Autobiography 4.4 SDV8
Previously George a 2007 MY07 Java Black VSE 3.6 TDV8
Previously a 04 MY04 Defender 90

one of the main reasons why I have this Hilta 3000 jump pack in the back of my car - only had to use it 3 times in five or six years, but it paid for itself easily many times over

So it doesn’t give you any warning about low battery first? Just sort of gives up? 2025 P550e AB

Mine didn’t when it was really low no, it did exactly as you describe and when I checked battery voltage was low, after a charge it was absolutely fine. Worth checking IMO

It does when it’s low and needs the engine starting though. MY17 Santorini Black L494 Autobiography 5.0 SC - Sorry!
Previously Bell a 2015 MY16 Loire Blue Autobiography 4.4 SDV8
Previously George a 2007 MY07 Java Black VSE 3.6 TDV8
Previously a 04 MY04 Defender 90

Thanks so much for all the advice.

Tried one more time and now the brake pedal judders under my foot.

Plugged in a ctek and it’s telling me it’ll be 6 hours to charge back up, basically proving that the battery isn’t happy.

It’s a late 2018 car so could be on the original battery. I’d have a look but I’m not really sure where it is given it’s the PHEV 2025 P550e AB

Get one of THESE, and use it regularly with your new replacement battery, Range Rovers eat batteries like you eat a packet of crisps:

￡17.61 40％ Off | KINGBOLEN BM580 Car Battery Tester 12V 6V CCA Circut Tester Cranking Test Charging Tool BM550 Automotive Battery Analyzer Kw208
https://a.aliexpress.com/_EuiL09N

 V6 Vogue - “Less is More” - less to go wrong!

AnnualMan wrote:

So it doesn’t give you any warning about low battery first? Just sort of gives up?

It also depends on weather or not the tech switched battery monitoring on in the CCF during the PDI stage... We often find low coolant alarm, low oil level & pressure are all switched off in the CCF menu!

Just wanted to report that alls well and the ctek seemed to breathe life back into the old girl. Thanks again for all the helpful advice! 2025 P550e AB

Still worth getting the device I posted, it will confirm the % SOH of your battery, which I suspect will not last much longer, perhaps surprising you when most inconvenient. V6 Vogue - “Less is More” - less to go wrong!

I definitely will, thanks for the tip. Can I measure the battery from the terminals in the engine bay? 2025 P550e AB

Yes, no problem with that, no need to go into the boot.
I had a few weird electrical issues before replacing my battery last year, and the tool diagnosed my battery was down to 29% capacity! It was basically surviving on the permanently-connected CTEK, but needless to say as soon as Winter arrived problems got much worse.

As I’ve said, FFRR’s eat batteries for breakfast, and 4 years is about the going rate, especially if you have a single-battery vehicle with stop-start, running short journeys. V6 Vogue - “Less is More” - less to go wrong!

I would add that the best jump-pack of all is a decent, healthy main battery in the car itself.
The best way to jump start the car is by pressing the start button, surely? Especially if it’s raining!

I don’t see the point of flogging a “dead horse” battery with another er, battery? why not spend the money on a decent main battery to begin with? Appreciated if you have several infrequently-used vehicles they can make sense.

A good but cheap diagnostic tool will make sure you don’t waste money on a new battery due to other issues.  V6 Vogue - “Less is More” - less to go wrong!

Should I need then install a new battery, would I need a tool to ‘tell’ the car? 2025 P550e AB