L322 4.4V8d Westminster gone into melt down. Wont start.

After not being driven for 10 days or so, my TDV8 Westminster l322 has decided to have a prolonged rest.

If I try to start it the digital dash comes on, tells me im in low range and that there is a engine system fault and then shuts down again. Sometimes it sounds like the starter solenoid is trying to engage but the engine does not turn over.

Ive charged the battery over night, but that hasnt made any difference. This morning ive plugged in a basic "Foxwell" fault reader but that hasnt shown any codes up at all. Varta battery was made in April 2021 but the car has only done 65000 miles, doesnt get used much at all with me and probably wasnt used much with the previous owner either, so maybe that battery has run its course.

Could someone point me in the right direction of how to get the car running? There is a mechanic nearby but if I would like to try to address the problem myself if I can. Im near Warwick if anyone has diagnostics.

Now the car is absolutely stone dead ..... not so much as an interior light coming on....

You need a new battery?

New battery then startlooking at earth straps

Well let's hope it's an easy fix and just a battery as you both say. Will get one ordered tomorrow. Thanks for your responses

Have you checked the battery? It's a reasonable age for a battery though, especially if it's not looked after