I have a 9 month old P400e that will not power up when I press the start/stop button. I drove it a week ago and it was perfect, went out yesterday morning and the door locks open with the keyless entry and the interior/exterior lights come as normal. The dash and center displays are completely dark. I thought the battery might be low so I measured the voltage - it was showing at 12.5V so i put in on charge overnight and it's now at 12.6V (=100%) and still nothing. I tried the second key and it made no difference. The boot will open and close on the button or key fob so there's enough power for that, there's no Low Battery warning or any other warning symbols. Tried jumping cabling to another battery.

When I sit into the car and hold the brake pedal while pressing the start/stop button the red parking brake light symbol flashes on the dash but nothing else comes on. If I keep pressing the start/stop button the brake pedal starts to move/make a noise like the ABS is working!

I have an Autel OBD scanner which I have tried but it won't connect because the car ignition is not coming on!

I work in medical device manufacturing company and I still need to go to work every day - currently using the Mini.

The dealers are all closed so all help gratefully received! Current: RRS P400e PHEV HSE Dynamic MY19.5 Santorini
Current: Mini Cooper SE Electric 2022
Current: Discovery D300 SE Commercial MY24
Gone: RRS 3.0TDV6 HSE MY 17 Santorini

If you'd had it on charge over night and it only showed 12.6V, that would suggest that the battery has a problem. If you tested it just after taking off the charger, I'd expect the voltage to show about 13.5V (or more, depending on what the charger was doing at the time you removed it). That's because you get residual surface charge on the plates in the battery giving a spuriously high reading immediately after charging.

I had a battery that would show similar after charging but as soon as it was asked to do some work (starting the engine), the voltage would drop to less than 11V showing a dead cell. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Are the LR assist not working.?,I know the likes of AA & RAC ect are working. Andy.
21 Ford Ranger
Gone but not forgotten
Focus RS Red Edition
2015 RRS AB Fuji.
2014 RRS SC Santorini
2016 VW Amarok
2014 RRS AB Fuji
2012 RRS Red Edition Fuji
2015 Nissan Navara
2012 RRS SE Santorini
2008 RRS White
2007 RRS Santorino

Thanks guys, I'll check the battery voltage again after it's been off charge for a while. Andy, I'll give Land Rover Assist a try and see if there is still support available? Current: RRS P400e PHEV HSE Dynamic MY19.5 Santorini
Current: Mini Cooper SE Electric 2022
Current: Discovery D300 SE Commercial MY24
Gone: RRS 3.0TDV6 HSE MY 17 Santorini

This shows how a battery is charged or not

Thanks Lindad, I am getting 12.4V and the boot lid won’t open under power, it will close once I open it manually. So I’m guessing that I have a dud battery. I’ll contact Land Rover Assist tomorrow. I’ll also try jumping it off my wife’s Discovery 5. Thanks again. Current: RRS P400e PHEV HSE Dynamic MY19.5 Santorini
Current: Mini Cooper SE Electric 2022
Current: Discovery D300 SE Commercial MY24
Gone: RRS 3.0TDV6 HSE MY 17 Santorini

Something more going than the battery. I connected it to the Disco 5 with jump leads and the car will still not power up!
Will keep you updated as I work my way through this one - it could take a while with no dealerships open! Current: RRS P400e PHEV HSE Dynamic MY19.5 Santorini
Current: Mini Cooper SE Electric 2022
Current: Discovery D300 SE Commercial MY24
Gone: RRS 3.0TDV6 HSE MY 17 Santorini

You may have a parasitic drain which is bringing your battery down. More than likely with only a 9 month old car. I had that on mine.
Battery kept showing low readings. Took it to dealer who said nothing wrong, drive it more. Took it to Auto electrician who eventually found it. No problems since.
Just read your latest post, looks like more than that. Take it your battery terminals are tight?

Yes, checked connections - they are ok. The headlights switch on from the key fob and look normal for brightness. I am wondering if a fuse is blown, will do some more research tomorrow! Thanks again for the suggestions.. Current: RRS P400e PHEV HSE Dynamic MY19.5 Santorini
Current: Mini Cooper SE Electric 2022
Current: Discovery D300 SE Commercial MY24
Gone: RRS 3.0TDV6 HSE MY 17 Santorini

Possible dodgy/loose earth connection somewhere? 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Success!
I did a tour of the fuse boxes looking for a blown fuse. When I got to the fuse box behind the glove box and pulled FL1 to check it a warning message came up on the dash saying the reversing sound would not be available. I put the fuse back in and the car came back to life! No real logic for any of this but I am just happy I didn’t need to have it transported to the dealer. I drove it around the yard and everything seems ok - will drive it to work tomorrow and make sure. Thanks again for all your help. Current: RRS P400e PHEV HSE Dynamic MY19.5 Santorini
Current: Mini Cooper SE Electric 2022
Current: Discovery D300 SE Commercial MY24
Gone: RRS 3.0TDV6 HSE MY 17 Santorini

Great news.

One to add to the canon of "what's gone wrong in a weird way this time?".  2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Good job you had the Mini PHEV to fall back on.......  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

Uk dealers have been offering a non contact service for those in key worker positions (had an email a couple of days ago). Range Rover Sport HSE DYnamic SDV6 Velocity blue 2020 MY
Range Rover sport HSE Dynamic P400e Silver
Range Rover Sport 3.0 SDV6 HSE Dynamic 2016 MY
Range Rover sport 3.6tdv8HSE 2007 Gone
Range Rover sport 2.7tdv6SE 2005 Gone
Range Rover sport 2.7tdv6SE 2007 honey
Range rover Vogue 2005 4.4 - GONE and missed
BMW 535d M sport 2006 - GONE not as missed
BMW X5 4.4 2004 sport - GONE

Yes Tim, the Mini is brilliant - hasn’t let me down! I drive it 2/3 of the time to keep the mileage down on the RRS.
I got phone support from the dealer but no real suggestions other than phone Land Rover Assist - I tried them but they were just going to transport it to the dealer that wasn’t open. Glad I got it going myself. Current: RRS P400e PHEV HSE Dynamic MY19.5 Santorini
Current: Mini Cooper SE Electric 2022
Current: Discovery D300 SE Commercial MY24
Gone: RRS 3.0TDV6 HSE MY 17 Santorini