I have read many posts where Yorky Bob has given good advice about making sure that you have a reliable battery and have it well earthed.

I would like to add to that there is a need for a heavily digitalised vehicle, like the FL2, to have good earthing to all its modules and components.

Any variation of either it's power supply OR EARTHING will cause signalling problems between units.

Add to that slightly corroded connections between units and you get intermittent problems.

I believe the FL2 does need proper diagnostic equipment and fault finding. It doesn't seem to me that it will survive getting bits from the scrapyard for very long. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 77k+ miles) (MY2015)
Metro in its 11th Year of (Extended) LR Warranty / Full LR Service History
(Expensive, but Trouble/Worry free - hopefully?)