Join Date: Apr 2010
Ferrari Life Posts: 2,203
Jack, you might have a look at the 550 WSM and its wiring diagrams. Sometimes it's helpful, as are the wiring diagrams from the 355 manual.
I usually start the electrical diagnostics by trying to get my head around what they were thinking (and sometimes THAT'S a real challenge) then I break out the DVM and start the point to point process.
'99 550, Rosso Corsa / Nero, S/N:114654, Assy: 31836, Engine: 52084
High mileage, low compression, and missing on a few cylinders.....just like my cars.
Maranello Skunkworks Team Member