Technical Fiat coupe 20v turbo wont run

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Technical Fiat coupe 20v turbo wont run

Aug 22, 2022
Hi gentlemen,

So my fiat coupe 20v turbo is having a few problems.

Literally the day before viva italia show the central locking began playing up and going weird. When unlocking with the remote it would do the opposite. Then I began using the key but you could feel the central locking motor moving while holding the key in the lock position. Thought ok I'll fix it soon as I get time.

So next the horn I noticed wasn't working say middle of last week but as I work long hours I can't fix anything on the car till the weekend.

Get to this weekend and I put power to the horns and they both work. Got the wife to press the horn and got no power at the wire connectors. It started raining and I went to put my window up and the windows wouldn't work and the dash instrument cluster was dead.

Checked fuses under dash and a service fuse of 10 amp was blown. Wiggled relays abit but the car still wouldn't start or windows go up.

Closed the fuse box up back under the dash and then tried again and the windows started working and car started fine. That was Saturday.

Went out to the car about an hour ago and went to start it and it's back to not starting, windows not working and dash instrument cluster dead.

Car turns over but won't fire. Can't hear fuel pump noise. Haven't got any time now to diagnose until weekend but if anyone has any ideas/suggestions please let me know as I'm stumped.

Ive had a quick look online and saw about some yellow connector of death but dont know where its located. Saw online about the fuel inertia switch being under the dash on the a pillar area but dont understand how it could of been activated. Also theres some kind of yellow box thing behind the dash people online were talking about but yeah if anyone out there can help i would be very greatful.

Thanks in advance

The car is my daily so it's a difficult situation to be in.
I would start by removing and cleaning all the fuse and relay pins particularly under the bonnet. I don't mean a spray clean, use wire wool.

Secondly, what is the voltage reading, car turned off, on your battery?
Hi gentlemen,

Can anyone confirm on fiat coupe 20v turbo is this the yellow connector of death?

Looks OK to me. No melted or burned out wires.

When I turn on the ignition I think I can hear the fuel pump priming noise.

I dunno if it's an immobiliser problem or what.

Any ideas send them over. Won't be able to remove and clean all fuses till weekend as I get home quite late during the week from work.



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Yes that looks like it - right side of drivers foot well, the only yellow connector there.

It will not however cause all the problems you have listed; windows, central locking etc as it is the main 12v supply for the fuel pump only. I would start with the easy stuff like cleaning all the fuses and relays and then if no change, cut out the YC and join the wires. In the meantime you could unplug it and take a look, does it look burned, could it be causing a high resistance?
Afternoon gentlemen,

Coupe is still dead.

I've taken out every relay and fuse from fusebox and cleaned every metal contact with a wire brush- I think it was approx 100 contacts I've cleaned.

Still dashboard,windows,central locking
remains dead and car will not start.

I'm sure I can hear the fuel pump prime when ignition is turned on. The hazard lights work though which is weird.

I saw online it said about disconnecting the battery, removing the fuses under the bonnet for inj and efi for 15 mins and once you connect everything back it resets and you can start the car. Well that didn't work either and I left it disconnected for about 2 hrs while I was wire brushing the fuses and relay contacts.

Under the bonnet I found a green 30 amp blade fuse holder that looked crusty. Upon trying to remove the fuse it crumbled and fell to bits so I had to fish it all out of the holder. Have ordered a replacement.

Under passenger side of dashboard I found the fuel pump relays and 2 more blade fuse holders both with 20 amp fuses but one was melted so I replaced that.

Car still refuses to start. I've got a auto sparky booked for a few weekends time to hopefully come and save the day but I thought I'd try do the basics and maybe get lucky.

Does anyone know if its possible to get a physical printed copy of either a wiring diagram or some type of haynes or workshop manual for the fiat coupe 20v turbo? If so let me know.



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The coupe lives again!!

Got an electrician out today(had to wait 3 weeks as he was booked up) and as he was going through his checks he noticed a plug on the back of the fuse box had walked itself out enough to no longer make contact but wasn't that far out that it was dangling if that makes sense.

Soon as he sorted that the dash lights all came on, windows worked and I said fire it up and wallah back in business!

He also fixed my horn that had given up and had a look at a central locking problem.

If anyone needs electrical work doing the guy I used was Dave Aces auto electrician tel 07763647203. Very knowledgeable guy, fair pricing and he even does air con so I got the air con pressure tested and re filled so it's ice cold. I'm honestly over the moon now I've got my coupe back