Why is it so important to have an in-line fuse when you install an amp (or else) that already have a fuse in it? To protect the line itself?

Well why don't the car manufacturer use fuse for power line then? I never see any fuse between the alt and the batt and for those who have done the BIG3 I'm pretty sure they didn't install one... What am I missing here?

 

Very good point.
I believe the main reason is that in car audio you have to run the wire through the firewall. In a collision, the firewall is much more likely to slice through the wire jacket than any engine components . . . that's all I can think of.

 

Good point or if there's a fire in the engine compartment the firewall is there to "protect" you while you get out of the car...

In case of a fire caused by a electrical problem, will the insurance company refuse to pay because you added cable in the engine compartment or elsewhere ?

 

Most manufacturers use fusable links between the alternator and the battery...... People who do not fuse their big 3 link are just asking for trouble if you ask me, in this day and age there is no reason not to have proper fusing in a daily driven vehicle.

 

Really? Unless they hide it in the wire, in my Caravan the wire goes directly to the battery...

I am asking this bc the other day the Caravan of one of my neighbor catch fire (pre 2000 model)... No aftermarket component was installed and the car was parked and not running...

 

It is indeed buried within the wire and to the untrained eye, it looks exactly like wire. For a fire to have started in a parked car..... something much more than a lack of fuse or fusable link is suspect.

 

Cool

You see that's what I love about life, you learn things everyday!

 

If you want to see what a fusable link looks like, head into any auto parts store and ask to see one. You will see how easy it is to overlook once you know what it looks like.

 

usually that 2-3" of heatshrink near the end of the wire is hides the fusible link so it looks just like a section of heatshrinked wire.

Fusing is ALWAYS a must. and as absolutely close to the batter/alternator(for big 3) as possible. The fusing is there to protect the wire, not the amp. SO many times have I seen people with the in-line fuse just inches from the amp and nothing at the battery and the power wire run through the door jam so it gets crimped every time the door closes. ahh good memories. Specially the one with the really big burn hole through the metal in the kickpanel/door jam.

A Forgotten fuse on a battery reloaction job at a performance shop here in montreal resulted in a melted RSX type s

 

The caravans were prone to leaking powersteering fluid which would fall on the exaust and catch fire. that is the most likely cause of the fire. The manufactures do protect the wires, they are fused in more than one place(fusable links,fuse box,breakers) You think that they want to be liable for a death that they could prevent by fuses?