456 circuit board and fuel pump

No

I suspect there was arcing at the contacts in the connector which caused the burnt connector but the current draw did not exceed the fuse capacity. This could be caused by corrosion in the contacts.

Most likely not.

 

Actually it makes complete sense to me. I've seen it a hundred times. I wrote out a page long explanation why and lost my internet connection so it went up in smoke. Not doing it again.

 

Ya mean I'm wrong? that'd be a first

 

Fuel pumps are the biggest load on that board at a 100% duty cycle. A new pump draws 7 or so amps, a bad pump can draw enough to blow the fuse or just a little less. That board and those connectors cannot handle 14 amps on a 100% duty cycle and 14 amps will not blow a fuse. It may not have been a perfect connection to start with but that probably describes 25% of the connections in the car.

China syndrome. Just what you have. Not uncommon in a number of makes but for a couple of hundred no one cares. For a couple of thousand people start caring.

It is not a pump problem for certain but for certain a pump problem can cause that. Been seeing it since Budda invented fuel injection. Manufacturers still cannot get over buying electrical equipment at Radio Shack. It is intended to be just good enough for the average new car buyer. On month past that date and they spent too much.

It's why we'll never buy another new car. 10 times as much of the same bad stuff. Digital malfeasance.

 

I have owned three 456 cars, and
always enjoyed driving them.

The fuel pump "system" is a known problem,
and can leave you on the side of the road.

The "rubber vibration dampers" that surround
and protect the fuel pumps deteriorate over time.

The debris created passes into the pump output,
and can fill or clog the down-line filter.

If any of the crud gets past the filter,
it will quickly clog the injectors.

If the injectors clog, not-running will
be the least of your problems. High-speed or
dyno running may cause cylinder(s) to run
lean, and burn pistons (s)

I have changed the pumps, dampers and filters
IMMEDIATELY on every 456 I have owned.
(When doing this with a "non-M" model, I
take the time to "reshape" the gas tank
baffles so as to NOT get the
"false low fuel" reading.

Cut open the fuel filters and see if they are beginning
to clog with the "black death, and then decide
whether or not to pull the pumps.

If the black death is showing in the filters,
you better pull the fuel pumps.....

If I was not willing to immediately commit to new
fuel pumps (That's almost $1,000 for parts), I would
AT LEAST automatically replace the rubber dampers.

You might check the "draw" of EACH
fuel pump with a suitable ammeter......

 

A question when were the pump vibration mounts last changed?

 

The fuel pumps & radiator fans should have been wired separately from that main fuse/relay board.

As Brian and others have said, the connectors are not really rated for those loads, and as soon as the connections heat up & start oxidizing and forming carbon, the situation goes from bad to worse.

Ferrari's wiring & electrics are nearly as bad as the British (Lucas) were in the 60's and 70's.

 

In fairness to Ferrari there are a number of other makes out there with similar problems. Years ago we saw it on some other European makes and I understand it is not all that uncommon on a number of later cars. Like I said, when a new fuse panel costs $200 and a handful of connectors is another $5 no one really cares.

As far as the fuel system parts mentioned above, I know of several high mile, driven every day 456 and 550's out there that have none of these problems. I am doing a complete overhaul on the fuel system of a low mile Mondial that has been sitting for years. Anyone seeing a pattern? Can't blame a car manufacturer when we subject the product to every type of use that causes failure. Low batteries, overtaxed and often partially compromised alternators and gee, now we have electrical issues. Not real hard to see in many ways we don't give the cars a chance.

Not saying these cars don't deserve some criticism but their worst enemy is us.

 

Come on Brian, don't go getting soft on us Tell us how you really feel about Ferrari's electrics and schematics

 

The schematics on that era of car suck but I will happily take Ferrari electrical systems over many other even mainstream cars. There are a lot of very bad ones out there.

Did you ever hear about the enormous number of Mercedes Benzs whose harnesses were made from reclaimed copper? They used an acid wash that was not totally neutralized and the copper just rotted in the insulation. Strip the insulation in the middle of the harness somewhere and it was just green dust. Benz spent millions replacing harnesses if you complained enough. The rest just got screwed. There are huge fright stories on Saab electrical systems. And can buss systems? Holy crap. Lots of cars out there have had huge issues.

 

As a very long sufferer of Alfa disease...far too many to admit, what Brian says about all these electrical gremlins is understated, kind, and can't quite convey the real scope of the issue.

Italian electrons have proven over time that they aren't the sparkiest in the jar. I used to say that the Alfa harnesses had little labels telling the 'trons to "turn left here". Switch gear is the absolute worst. Critical running electrics from the likes of Magnetti Marelli weren't so bad unlike Lucas "Prince of Darkness" stuff or Smith Bros. heaters but the switch gear is just the absolute worst!!

Old joke...Why do the Brits drink warm beer?........Lucas Refrigerators.

Ital corollary...If Meatloaf had driven an Alfa, he'd of never written "by the dashboard light!"

 

OK I m curious what reshaping did you do?