Circumventing fusebox

On my '87 beater, a couple of the places on the fusebox where fuses plug in are FUBAR, like someone squashed and destroyed the little brass connectors in there. We're talking the heater blower and the rear window wiper here. The rest of the fusebox is still good, and the Jeep's an auto so no clutch fluid worries or anything.

The fusebox is scary. I took one out of a junker the other day just to see how it's done. The answer is, "not very easily at all." I think I'm uncomfortable trying to switch it out with a less beaten-on one. I am no electrical genius.

That being said, this next question might prove it. Can I run a sufficient gauge wire from battery positive to the blower directly, using an appropriate inline fuse, thereby circumventing that part of the wiring harness/fusebox? You know, just sort of treat the blower as an aftermarket accessory? Or would I be all-too-literally playing with fire?

If I can do this, how would I make it so the blower still only works when the ignition's on? Relay triggered by a wire spliced to another wire that's only hot when ignition's on?

This feels like a plan that must have some reason it won't work. Or am I just being a big ol' pussy about the fusebox?

kristuphir said:

That being said, this next question might prove it. Can I run a sufficient gauge wire from battery positive to the blower directly, using an appropriate inline fuse, thereby circumventing that part of the wiring harness/fusebox? You know, just sort of treat the blower as an aftermarket accessory? Or would I be all-too-literally playing with fire?

If I can do this, how would I make it so the blower still only works when the ignition's on? Relay triggered by a wire spliced to another wire that's only hot when ignition's on?

This feels like a plan that must have some reason it won't work. Or am I just being a big ol' pussy about the fusebox?

Click to expand...

You could do it like you said and just run a new feed wire with an inline fuse of the correct size.

But, can you get to the wiring coming into the fuse box? If so, locate the 2 wires going to each of the fuses you want to replace and cut them off. Then add in an inline fuse holder (the type with lead wires coming off it) and crimp or solder it in place, then fuse it the same size as it was in the fuse box. No concerns about new feed wires and stuff that was ignition switched before is still switched. I've done this on another make/model of car that was notorious for melting fuseboxes.

Mark N

Actually this will be the perfect chance to do the relay mod that others have done after the current draw from the blower melted their ignition switch. So no, you are not playing with fire and possibly preventing one.

Probably the simplest way to do this is to use the accessory wire from the ignition switch (probably brown or purple) as a trigger for a relay. Cut that wire and switch it with the relay as you suggested. A 30 amp relay is probably adequate but it wouldn't hurt to go ahead and use a 40 or 50 amp unit since they cost about the same. I would probably use 10 awg wire and 30 amp fuse from the current source.

Not high tech but you can find several threads relating to this mod six months (or longer) ago. I know Ecomike was one of the members involved.