Help - box on top of battery with fuses in it

[johnjohnhealy]

That black wire is the alternator wire.

Quite often burns out if the alternator starts over charging, only seems to happen on the 1.8T's. I have changed a few cables and alternators because of it.

It's a common fault on the taxi's too, normally the 1.9 sdi's, you can keep replacing the fuse thing but the problem will re-ocur until you fix the cause of the problem not the effect.

[Octygone]

Being an electrician I was going to say it's all very fixing the fuse....but it would be far better to fix the problem as well, after all it didn't melt for nothing

[TKW]

Being an electrician I was going to say it's all very fixing the fuse....but it would be far better to fix the problem as well, after all it didn't melt for nothing

I don't think anyone's particularly sure what the problem is, though. Most likely culprit seems to be corrosion. I wonder whether it's got anything to do with the fact that current is flowing a different direction in the black cable compared with the rest? Or maybe that the black cable is just closer to the outside and gets damper? In either case, the fuse isn't melting so much as the casing burning around one of the contacts.

[Octygone]

I don't think anyone's particularly sure what the problem is, though. Most likely culprit seems to be corrosion. I wonder whether it's got anything to do with the fact that current is flowing a different direction in the black cable compared with the rest? Or maybe that the black cable is just closer to the outside and gets damper? In either case, the fuse isn't melting so much as the casing burning around one of the contacts.

To be honest that sounds like a loose connection....either on the terminal intself or the "eye" fixed to the cable isn't tight enough....and as it's only happening on one end (the same end by the look of it) it all points to a loose crimp connection on the "eye"...this would heat up and melt the plastic

[will_]

A higher current would cause that connector to heat up more (and there'd be a significant current all the time), causing the ends of the wires to sinter where they're exposed to the air. This would cause the connection to become high impedance (high resistance), causing it to heat up further, and so on, until it fails completely. Crimped connections are particulaly susceptible to this.

Maybe they included a fuse in case the wire from the alternator touches the chasis - that would short out the battery without a fuse.

[cookie-859]

Have just been trawling through the threads,and I have just had the same problem 6 months later and Skoda don't seem to do nothing about it!!

[AcW]

i Had the fuse box to bits this morning and cleaned everything up as much as possible, the nut for the wire has burned the bottom of the box and fallen out, so new fuse box on order (

[4x4t]

Somethings wrong with the alternator,should give over 14volts when running.Or there is a very bad connection somewhere.

[WelshLoon]

Wondering if this caused the battery area fire on my Vrs, when i popped the bonnet the fire was on top of the battery, no water or anything else in the car to put it out and it spread pretty darn quick

[Tech1e]

Sounds like it, done a few now on 1.8T's not just Skoda.

Do like the advice of ditching the fuse though and wiring straight to the battery, sounds like very sound advice. Perhaps we can apply that to all fuses then we wouldnt ever have to replace one again..lol.

9/10 times its a knackered alternator that is over chargring and melts the wire down. Either get the alternator repaired or replaced. Also replace the loom and fuse box. Th other 1 time has been because the 10mm was left loose, poor contact means excessive resistance or sparks and melt down.

Might be worth letting a Skoda dealer or customer services know (just an idea). They do take fire hazzards very seriously. You probably wont get any help financialy from them but it all helps them realise there is an issue.

[cookie-859]

Sounds like it, done a few now on 1.8T's not just Skoda.

Do like the advice of ditching the fuse though and wiring straight to the battery, sounds like very sound advice. Perhaps we can apply that to all fuses then we wouldnt ever have to replace one again..lol.

9/10 times its a knackered alternator that is over chargring and melts the wire down. Either get the alternator repaired or replaced. Also replace the loom and fuse box. Th other 1 time has been because the 10mm was left loose, poor contact means excessive resistance or sparks and melt down.

Might be worth letting a Skoda dealer or customer services know (just an idea). They do take fire hazzards very seriously. You probably wont get any help financialy from them but it all helps them realise there is an issue.

I am currently in contact with Skoda so we will have to see the outcome of my query.

[cookie-859]

Well here we are again,a little bit older,but none the wiser!!!

The latest reply from Skoda that after careful consideration they regret that they are unable to offer any goodwill.No surprises there then!!

The fact that the car was taken to a none Skoda retailer network. I thought that after 3 years you can take the car anywhere to get it fixed.The next step is to contact the Customers Affairs Dept. in London.Don't hold you breath.WILL KEEP YOU INFORMED.

[cookie-859]

Sounds like it, done a few now on 1.8T's not just Skoda.

Do like the advice of ditching the fuse though and wiring straight to the battery, sounds like very sound advice. Perhaps we can apply that to all fuses then we wouldnt ever have to replace one again..lol.

9/10 times its a knackered alternator that is over chargring and melts the wire down. Either get the alternator repaired or replaced. Also replace the loom and fuse box. Th other 1 time has been because the 10mm was left loose, poor contact means excessive resistance or sparks and melt down.

Might be worth letting a Skoda dealer or customer services know (just an idea). They do take fire hazzards very seriously. You probably wont get any help financialy from them but it all helps them realise there is an issue.

SEE MY LATEST.

[Tech1e]

You can take your car anywhere to get fixed. Only dealers can do warranty claims.

However should you want goodwill outside of the warranty period a full dealer history carries a lot of weight.

[phillip]

Had this problem on mine about 3 weeks ago (after changing the alternator about 3 months ago - possibly un-necessarily ???), and found an easy fix..... if you prise the nut off the end of the black cable using a screwdriver, the eyelet on the end of the cable will then slot straight on to the front bolt on the positive battery terminal :D.

Working fine now .

[goodridge]

That black wire is the alternator wire.

Quite often burns out if the alternator starts over charging, only seems to happen on the 1.8T's. I have changed a few cables and alternators because of it.

I'm soo glad you said that. I've got a MK4 Golf in at the moment with this very problem. Have replaced the battery box, but assumed I had a charging or a dead short problem. Haven't finished looking at it yet. Best get the alternator off and tested then

[goodridge]

Guys is there any more info on this? I had the alternator tested today and they said they can't fault it whatsoever. I Can't see much point in replacing the lead as I measured the resistance at next to nothing ?!

[AcW]

check the contact with the fuse, if you get a high resistance at one point it will heat up and melt the plastic case, as happened to mine, the fuse wont blow as the current will never get high enough but it will eventually case a fire if left!

great design.

[cookie-859]

Hi AcW,sorry for the delay but I have been away on holiday.Skoda have replied and still deny any responsibility as it was repaired by a non Skoda garage.This was after the 3 year warranty.Also their technical Dept. are not aware of the problem! I have got an address from my original paperwork which is a Consumer Affairs Dept.so I am going to drop them a line.WILL KEEP YOU POSTED.

[KenONeill]

Can I just comment on a couple of generalities raised?

1) Fuses sometimes blow from old age. I'd only presume an underlying fault if I had to replace the same fuse twice in quick succession.

2) Fuses are often over-rated for the nominal feed/draw for the kit. They're selected on the basis that they need to handle C amps, and Rating1 < C <= Rating2.

[Pudsey83]

I had this problem, on my 1.9 SDI, the lights all came on so the dash looked pretty but car had no power.

I changed the base plate and the fuse and asked skoda what could of caused this, all they said was that their mechanic had seen it a few times before, and all cases seemed to be caused by the black terminal coming lose and the red one closest to it arc-ing causing the heat and melting the plastic.

Since had all changed i've had no problems since.

So maybe worth checking to ensure all terminals are tight

[arnold]

I had the exact same thing just before christmas. The car faulted on a couple of occasions and would not start so i replaced the battery. Worked ok for a couple of weeks then all the lights on the dash illuminated and the speedo needle got stuck then the car died. Turned out it was the alternator which in turn fried the fuse box on top of the battery. Total bill was about

[cookie-859]

Hi AcW,sorry for the delay but I have been away on holiday.Skoda have replied and still deny any responsibility as it was repaired by a non Skoda garage.This was after the 3 year warranty.Also their technical Dept. are not aware of the problem! I have got an address from my original paperwork which is a Consumer Affairs Dept.so I am going to drop them a line.WILL KEEP YOU POSTED.

Well here we are again.Sadly no further on.I have had a reply from the SMMT New Car Code of Practice Concilliation Service who ramble on and actually don't say a lot.This actually refers to problems with new cars,but what I am furious about is that from the input received on this forum concerning a whole range of the Skoda/VW family there was,and who knows there still could be an inherent fault with the alternator/fusebox/battery set up. I don't accept for one minute the theories of loose connections and high resistances,when you read of the amount of contributors who have had this problem.

I am not sure as what to do next,but keep up with the input with this problem,as a problem I believe it is.

[AcW]

Hi cookie

The problem is one i have seen before on household electrics, medical equipment and my car. the problem is too high a current through a poor connection causing heating and eventually failure or fire. The answer is better design and vag don’t want to do that as it will cost money, if you have a look at a vag car in a couple of years time i bet the box will be different. What worries me is that my wife’s 18 month old car has the very same parts in it.

Buy Japanese next time

p.s my air con has packed up again :((