Mechanics

BATTERY FUSE BOX

2003 Volkswagen Beetle

Electrical problem
2003 Volkswagen Beetle 4 cyl Front Wheel Drive Automatic 65000 miles

While driving the car will shut down and not restart untill jumped. It will then run fine for days, then do it again while driving. I had the battery, alternator & starter checked ok. Upon inspection all I can see is the fuse box that sits on top of the battery has a wire that melted some plastic. The red wire is the feed from the battery. Right below it is a black wire connected with a 110v fusibile link, that is the one that melted somewhat. I was told this goes to the starter. I checked and nothing appears loose. If I hook everything up it will start. I was going to replace the fuse box for $100 but dont want to ruin that one and not fix the problem. Any ideas please!


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Bright1240
November 4, 2010.




Hi bright1240,

Thank you for the donation.

Engine stalling and not cranking until jumped indicates a fault with the charging system.

The fuse is for the alternator and not the starter therefore replacing the fuse box should solve the problem.

When terminals overheats, the most common cause would be improper tightening resulting in loose contact and heat build up. Over time the terminals would melt the plastics surrounding it.

After replacement of the fuse box, ensure the terminals are securely tightened and does not heat up when engine is running.

KHLow2008
Nov 5, 2010.
So the initial problem was loose contacts? If I replace the fuse box, tighten all contacts and it happens again what could it be then? Thanks so much, I will leave positive feedback!
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Tiny
Bright1240
Nov 5, 2010.
Yes, the most likely cause would be loose contacts.

If contacts are secure, they should not overheat unless the capacity is lower than required. That would mean the wire is not large enough for usage and could only be due to a design fault.

KHLow2008
Nov 6, 2010.
Hi again, I just wanted your opinion on something. I replaced the fuse box and fusable link and wrapped the wire going out to the alternator with electrical tape. It was cracked a little were it got hot. I drove the car a couple days and then looked at the box. The tape on the wire I wrapped melted quite a bit, should I be worried its going to melt more? Why is the wire getting so hot, Could there be a problem with my alternator? Thanks so much for your help!

Tiny
Bright1240
Nov 16, 2010.

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