Alternator wire melted...

[Mr Blue]

Hello

Ive done a search and got some results but its not all clear. I have a mk4 1.8T 2001.

Today the black alternator wire has melted and lucky the fuse box (ontop of the battery) survived. Engine cut out. total loss of power. If I move the black cable, the engine will start.

a) Could it be the climate control causing this overload and melted the wire?
b) Is it just a case of a common faulty cable?
c) Alternator regulator faulty giving out too much amps/volts?

I did take the battery out to change the headlamp bulb a few weeks ago. Could it be a lose battery terminal thats caused this? Im sure i did the terminals up tight but might not be tight enough?

Has anyone got part numbers for the following
*alternator cable
*the fuse box

Thanks

[richw911]

I would say a faulty Alternator 

Not sure how you can check now its melted?

[tg1]

is the black cable earth or power?

my first thought was ropey earth? you getting any unusal problems with the electrics, dimming slow windows, rev counter jumping?

sounds to be shorting out, but i'm no car sparky

and to test it just replace the broken wire with one that is similar gauge, if it works - broken wire

[richw911]

is the black cable earth or power?

my first thought was ropey earth? you getting any unusal problems with the electrics, dimming slow windows, rev counter jumping?

sounds to be shorting out, but i'm no car sparky

and to test it just replace the broken wire with one that is similar gauge, if it works - broken wire

True a few lads have had dodgy earths 

[tg1]

could always use it as an oppertunity to upgrade them to thicker gauge, and maybe a voltage stabilizer?

dunno if it'll do much good mind but worth a thought. i think its pretty much just a bunch of extra earthing points

[Wazzzer]

my mate had this, replaced the fuse box and all is well. Apparently it can be caused by the actual cable breaking down and drawing too much current

[Mr Blue]

A bit of a crap design for a cable. Surely something is causing this cable to fail?

chers. Ill give that a go first

[Mr Blue]

Changed the cable. What a pain in the a5s of a job for just a wiring loom!

That 8mm P clip is a pain to get to without removing the alternator. Really cant stand working on the mk4

Under closer inspection the battery fuse box has also melted. Great