Subs and amp stopped working after 5 yrs

[RobGMN Premium Member]

You narrowed it down to the fuse, the fuse holder, or the connection of the wires to the fuse holder, just by confirming the voltage drop before and after that "break" in the wire.

 

[ThxOne Premium Member]

Connections also come loose over time.

 

[Deiimos]

As the others mentioned, likely a connection issue. I don' think I needed to post in this thread, but, since the forums need more posts to help the site.

I’ll add this: 4 gauge wire is pretty thick wire, the only way one end of it can be 14 volts, and the other end 1.8 Volts, is a bad connection. If you had something pulling 4 gauge wire to 1.8v, there would be melted wiring / smoke. The reason it drops from 14v to 1v, is because the amp is trying to turn on and the bad connection won’t allow it, as already mentioned.

If the voltage drops at both sides of the fuse holder, when measuring at the battery, the problem should be at the small piece of 4 gauge that connects the battery to the fuse holder, likely a bad terminal. Assuming the voltage is being measured properly.

What kind of terminal is on the end that connects to the battery?

And what style fuse holder does it use?

Crimped terminals and set screw style can have problems like this, even if the connections look okay, they may not be, heat cycles over time they can go bad. The cheap molded MAXI style blade fuse holders that the fuse plugs into, can overheat and go bad too, I avoid those style holders unless real low power usage. This is where photos of the wire install could help us see what exactly is being used and how it looks.

If you have CCA wire, you'll see if it is bad or not if you cut the end off to put new terminals on or whatever.

 

[Nelly762]

As the others mentioned, likely a connection issue. I don' think I needed to post in this thread, but, since the forums need more posts to help the site.

I’ll add this: 4 gauge wire is pretty thick wire, the only way one end of it can be 14 volts, and the other end 1.8 Volts, is a bad connection. If you had something pulling 4 gauge wire to 1.8v, there would be melted wiring / smoke. The reason it drops from 14v to 1v, is because the amp is trying to turn on and the bad connection won’t allow it, as already mentioned.

If the voltage drops at both sides of the fuse holder, when measuring at the battery, the problem should be at the small piece of 4 gauge that connects the battery to the fuse holder, likely a bad terminal. Assuming the voltage is being measured properly.

What kind of terminal is on the end that connects to the battery?

And what style fuse holder does it use?

Crimped terminals and set screw style can have problems like this, even if the connections look okay, they may not be, heat cycles over time they can go bad. The cheap molded MAXI style blade fuse holders that the fuse plugs into, can overheat and go bad too, I avoid those style holders unless real low power usage. This is where photos of the wire install could help us see what exactly is being used and how it looks.

If you have CCA wire, you'll see if it is bad or not if you cut the end off to put new terminals on or whatever.

Solved bad wire from battery to fuse holder. Works fine after replacing the wire.