This was a poorly, tired 300Tdi that was saved by a routine check.
300Tdi starting problems and fixes: https://www.youtube.com/watch?v=1xlNZW7LtL4
ROW wiring pictorial guide: https://www.lrworkshop.com/wiring-looms/defender-2002
LR Workshop: https://www.lrworkshop.com/
Instagram: https://www.instagram.com/lr_workshop/