The black wire inside the fuse box above the battery of my octavia looks like it got over heated and melted the cover of the fuse box which made the battery drain. I had to jump start my car.

i want to know to what this black wire is connected to ? also, why it got over heated ?

please reply asap how to fix this problem.

Joseph

It's a common fault on the octavia, the wire goes to the alternator. I replaced the fuse and the crimp connector on the wire end and it's been fine since. Make sure you change the connector as it'll only happen again if not

As Si says, it's a known issue. The crimp becomes high resistance and causes the wire to heat up and melt the fusebox. There's a new revised one from Skoda with a heavier duty crimp on it.

mine has done this again today on my 3rd wire and fuse box so i have made my own wire and fuse box with larger gauge wire and its own fuse in line

Ouch!

If mine goes, I'm gonna get one made up myself using proper swicthgear crimps. That should work I reckon.

@Si : What exactly causes the crimp 2 become high resistant ? Is it due to some fault of the car's alternator ?

I would guess a reaction between the metal of the wire and that of a crimp, or maybe vibration over time, or just poor crimping when manufactured.

It is not a fault of the alternator as such.

I don't know exactly what causes it I'm afraid, all I know is that Skoda Tech said to change the crimp as it'll do it again if not. Mines been ok since I changed it (about 3 months ago), hopefully it will have cured it. If not I shall get some thicker gauge wire and try that as others have said.

Edited 16 July, 201114 yr by sivrs

I've always fitted the new loom from the alternator and new fusebox, never had one re occur again.

I would guess a reaction between the metal of the wire and that of a crimp, or maybe vibration over time, or just poor crimping when manufactured.

It is not a fault of the alternator as such.

i went to a local mechanic so he connected the black wire from alternator directly to the battery and he said it wont create any more problem. It seems to be ok so far. has any one done same thing? and did it create any sort of problem

Thanks,

Joseph

i went to a local mechanic so he connected the black wire from alternator directly to the battery and he said it wont create any more problem. It seems to be ok so far. has any one done same thing? and did it create any sort of problem

Does not sound like the best of plans, unless a fuse is there too.... I suspect Skoda designed and manufactured it in a certain way for a reason, but maybe your mechanic knows better!

Your mechanic's solution I am sure is fine for a "get you home", but I would rather have a new fuse box (if melted) and a new black alternator cable (or re-crimp the ends).