[Mk2] [NA] Burnt out Rad fuse ... why?

[jonboy2199]

I wanted to reset the ECU earlier due to a poor fuel economy issue and when I removed the fuse cover ...... I noticed that the rad fuse had basically melted away. Now I can't get the damn thing out without scraping it with something?! Even then what could I clean the contacts up with?

So my question is ... would this be due to a faulty/defective fuse or could there be a problem elsewhere?? Everything else is fine.

Cheers

[paul port]

A fuse is a very simple device, and as such has huge limitations.

You can expect a fuse to blow almost instantly when subject to a short circuit (100's Amps),
but when subject to a simple overload, it will likely sustain 2x it's rated current for several minutes or even hours, Especially those no-brand fuses (Why I always use LittleFuse or Lucas)
In overload, the fuse power dissipation is way above the norm, and can lead to melting.

In your instance, I suspect it may be Overload, or worse still, dirty / corroded / poor electrical contact. It doesn't take much resistance to generate lots of heat when something is passing >10A

Paul

[jonboy2199]

Cheers fo that Paul!

Whats the best solution to use to clean the contacts? Did I imagine it or can you use white spirits?

Cheers
Jon