kptknuckles

Hey gang,
Recently purchased a 1987 4runner, I was chasing down all of the blown fuses yesterday and have everything running well with the exception of two fuses under the hood,

7.5a charge fuse blowing when i connect the batt (-) terminal.

this has a tiny wire jammed in the connection, and runs to the haz/horn fuse, this is jammed in to that fuse as well.

The diagram says the haz/horn should be a 15a fuse
The one thats in there is a 25a fuse.

From looking around here my guess is that they wired it for power to the stereo.

Removing the wire and replacing the 7.5a charge fuse leaves the fuse in good shape but my charge light comes on and I know for a fact that this has been charging and running very well for the past few weeks.

replacing the wire and the fuse results in another blown fuse whoopee.

I have the full year specific FSM and wiring diagrams to follow as well as pictures, thank you thank you thank you to anyone who has a clue, I sure dont.

kptknuckles

there is a 5a fuse in place of the 7.5a charge fuse, I do not use this i just wanted to show how it was wired and ran out of 7.5a fuses

Redeth005

Oh man I thought I had a bad problem but yours seems a lot more confusing then the one I had. The last owner for my 89 4runner used house gauged wire in certain parts of the truck(solid wire and huge wire) luckily for me it wasn't tampered with in the main wire lines to the truck. It was just a huge crappy micky mouse job for the trucks so called "stereo system." I'm surprised this guy didn't burn the truck up when the truck was running.

I took it upon myself to rip out his entire ˟˟˟˟˟ty wire job and re do it all myself. So far all works fine. Only thing I cant figure out is 1 of the 2 power wires fir the stereo doesn't work and i don't know how to connect the wire to get power when I turn my truck on. The main power wire stays on but the one that doesn't work is the one that the truck tells the stereo to turn on when I turn the key to he on or acc position.
As of right now I just have a on and off switch that I connected straight to the battery that I can turn on and off whenever I want. Only problem with that is that every time I jump in my truck I have to reset my stereo settings because its like disconnecting the battery when I turn that switch off.

I know I didn't help you much. Just wanted to post this because I honestly don't know what the problem is. I know it just be an easy fix but I can't seem to figure it out. If you know what it is maybe yiu can help me out.

Duffdog

the charge light just lets you know if the field coil for the alt is working. I had to do that same thing on an older 4runner I used to have to make the battery charge. What happens is that the charge circuit is not energized prior to the fuse. Why this is, I don't know. But connecting the charge circuit to the battery directly allows the alt to charge. You might have a problem with the 2nd ignition circuit.

kptknuckles

Redeth as far as I know you just have to wire into an ACC line. A voltmeter helps obviously but my friend went right under the steering column for his, there is a wire in the original harness for this i believe that runs from the haz horn fuse, lightblue with yellow stripe on my 87
Duff do you think fixing my fuse box back to original will be dangerous? I know this is a workaround for something, I'll look into that ignition circuit tomorrow, but I can't figure out what.
Thanks guys

Redeth005

Thanks kpknuckles. I'll look into that when I get my truck back from the mechanic. I hope it works.

Duffdog

I would find out why there is no power to that fuse in the first place. Could be something as simple as a bad ign switch. Once you figure that out, you should be fine.

wyoming9

iTrader: (1)

It could be as simple as a corroded or loose connection in the fuse block itself.

If you have a loose connection that could be enough to cause the connection to arc drawing enough current to blow the fuse.

Inferno451

On my 87' 4runner the charge fuse kept blowing because the wires to the reverse light had chafed and were shorting out right next to the switch on the bent metal tab that holds them. That's definitely something to check out.

kptknuckles

Thanks for the ideas,
I'll be getting dirty tomorrow so I'll let you know how it turns out, thank you for the help!