Fuse off Battery? Positive or Negative?

warmblood58 · Post by **warmblood58** » 01 Mar 2016, 15:03

Noticed a black wire with 10amp fuse holder mounted to battery positive post -this should be a negative connect vs. a positive yes? I put a test light to it with ignition on and it would not light so I believe it is a negative connection, yes? Why the fuse here? Thanks! Schematic shows all red wires coming of '95 850 turbo battery so I am assuming PO installed wrong? Help!

Post by **abscate** » 01 Mar 2016, 15:56

You almost always fuse the positive side of a circuit since faults almost always occur to ground, or the negative side, through insulation failure or cuts. The only way to sort out hack wiring is to trace it from battery to the load. There are no end to the variations of bad wiring that can be done.

warmblood58 · Post by **warmblood58** » 01 Mar 2016, 16:11

Yes, but sometimes Neg connections are fused . . . I checked. Black wire vs red and it appears to be factory. Anyone know?

Post by **tryingbe** » 01 Mar 2016, 16:14

Sounds aftermarket. Post a picture.

warmblood58 · Post by **warmblood58** » 01 Mar 2016, 16:29

: IMG_1769.JPG (32.92 KiB) Viewed 788 times

Post by **erikv11** » 01 Mar 2016, 17:23

Never see anything like it from the factory, FWIW.

Post by **misha** » 01 Mar 2016, 18:51

Nope....it's not factory.
Could be for aftermarket alarm system,aftermarket stereo system like cd player,amplifier or some other accessories.

Post by **abscate** » 01 Mar 2016, 19:35

warmblood58 wrote:Yes, but sometimes Neg connections are fused . . . I checked. Black wire vs red and it appears to be factory. Anyone know?

Colour of wire is not an indicator of positive or negative. A negative fused circuit is only protected from component current draw, which is rare, vs. wiring failure, which is common.

That's a hack.