I've had 7 years of relatively trouble-free 159 driving and still in love with it.
However, with an NCT date that took 6 months to secure looming, I got a warning light each for number plate light and rear brake light on a long trip down to Cork.
No problem, stopped in a few places in the dead of night to find the right bulbs, but nothing doing.
Switching the good side light clusters / bulbs to the bad confirmed it was electrical, not consumable.
Back in Dublin I checked all the fuses, nothing, so we're down to wiring.
Stripped the boot area of all trim hunting down wires, in the case of the rear right brake light it turned out to one of many crushed wires in the bootlid loom. And its possible that the whole part was replaced in the past, because it still had its spare part sticker, in Italian on it.
The part number is 00505122020.
I've emailed AlfaPartsShop and John Linnane Motors in Rathnew in the hope they might help me locate a wiring loom, but the lack of search results beyond ebay doesn't give me much hope.
For now I've simply run an additional wire along the same route and spliced into the loom, but that's not the kind of repair the old girl deserves really, and there are definitely other wires in that loom that will suffer the same fate.
The number plate light fix was an even worse bodge, fixing that properly is a bumper-off job by the looks. I hope the NCT man will simply forgive it, I took the good +12v from the left hand bulb and ran it to the duff +12v for the right hand one. Didn't convince the CANBUS though, screen still says 'Check Number Plate Light'.
Very naughty splice for the number plate lights, I promise the car I'll do right by it soon.