Technical Replacing fusebox

[dado1975]

I had water in my fusebox and there's quite a bit of corrosion, now i have some electrical issues, surprise surprise. Anyway, the fusebox seems pretty knackered and not really something that looks to be serviceable.

Question is, if i get a replacement is it a straight plug in or does it cause some kind of programming to be needed. In other words, is a DIY job possible or do i need to see a FIAT dealer?

Some of you may remember my earlier thread on smoke from the fusebox. Well, i had planned on writing the old girl off but lack of funds and a couple of weeks as a pedestrian and now i'm looking to fix what i can and see if i can't get her back on the road for cheap. Advice appreciated as always.

 

[momoe]

Replacing the fusebox shouldn't required any re-programming. If you disconnect the ECU it should re-learn the parameters which takes a couple of days. Also make sure you have the radio code if it's coded.

Having said that it's not a job for the faint hearted, I'd try finding the source of the corrosion (Sunroofs, busted aerial mount, etc) first and then try cleaning all the fuse terminals using a small brash brush and electrical contact cleaner.
You might find a small vacuum cleaner useful, I use a piece of 10mm tube gaffer taped into my existing vacuum cleaner hose.

 

[dado1975]

Thanks for the reply Momoe. I know the source of the water (don't ask!) and have eliminated it. I did an external clean of what i could see first but no joy. I concluded the internals of the fusebox were corroded too.

I decided to have a crack at fixing up the knackered fusebox, if nothing else as a learning exercise. Now that is not a job for the faint hearted. Changing the fusebox is reasonably trivial as it happens, if you don't mind slicing your fingers to pieces due to the cramped workspace. Three allen bolts, remove all the connectors top and bottom, remove all the additional fuses hanging off the front and back and out it comes.

Not sure i'd ever recommend it, but i took the fuse box apart and cleaned it up, it was indeed a big gooey green mess. I can confirm there is nothing in the way of chips, switches etc in there so i'd say it's safe to say you are right there should be no re-programming required.

If anyone does ever need to do this job, i can tell you everything comes apart pretty easily. Just prise the various layers apart slowly and gently, the resistance is purely due to the various pins going through each layer, there is no other fixings to worry about. And i'd suggest you take pictures as you go in case anything falls apart and needs to be reinstalled in place! I have to be honest, i really didn't think it would all go back together again but it did.

Got a couple of pins broken off one of the connector sockets (too badly corroded), but otherwise i managed to get the job done and i'm back on the road

Haven't yet discovered what the broken pins relate to as nothing is not working as far as i've noticed so far! The blower and and fan were both broken before, as far as i know they pre-date the water ingress in the fusebox so not sure they are related. Having now got the proficiency badge in removing and reinstalling i think i'll get a new box off ebay anyway at some point then we'll see if they are.

Anyone know if there are electrics schematics that would go to the level of detail of what is connected to what pin? I'd like to know what my broken pins are supposed to be doing.

 

[widemouthfrog]

Do you know the fuse number for the one(s) with the knackered pins? Failing that, can you post a photo and highlight which one it is?

 

[dado1975]

Sorry, i maybe wasn't clear before. The actual fuses and fuse connections are fine, it's one of the connector blocks/sockets that go into the fuse box that is missing pins.

If you look at the attached external pic (pre clean up!) you can see the water entered through the socket in the top left corner of the pic and caused the mess in the second pic. If you enlarge the first pic you can probably make out that the pin 4th from top right in this socket is missing. One of the other ones broke off during cleaning too, i'd need to check which one.

I know that unplugging this connector stops indicators and brake lights working, but i have no idea what else. I know there are lots of unused stuff in the electrics, e.g. support for bluetooth, electric sunroofs etc which i dont have, but i'm thinking i just couldn't have got so lucky that the two missing pins relate to unused circuits (although i guess it's possible).