Mean Green hi output alternator fuse source

LTtaco · 10-26-2012, 11:13 PM

Hello, I'm working on my 04 3RZ-T and after adding a bunch of extra electrical powered goodies my OEM alternator proved to be inadequate. I have since purchased MG's hi output model and 0-gauge wire to accompany it. I have run the 0-gauge wire from the alternator to the fuse box where it junctions with a 120amp "cube" looking fuse labeled alternator (sorry I don't know the correct nomenclature for this type of fuse) and from there I have run another piece of 0-gauge to the positive battery terminal. I'm looking for one of those "cube" style fuses rated for at least 200amps. Does anybody have a source for these? I really appreciate your help.

To save some time on potential solutions, here's the current situation. I didn't account for this "cube" fuse being hard to come by when I began cutting OEM wiring, what I did was cut off the OEM power wire coming out of the fuse box running to the positive battery post. I have read that you are supposed to leave the stock power wires in place as well as the 120amp "cube" fuse, instead just run the 0-gauge wire and a big inline fuse straight from the alternator to the positive battery terminal. Thanks again for any help with this.

Enola Gaia · 10-27-2012, 07:23 AM

I'm not sure what you're doing ...

Are you wanting to replace the OEM 120A Alternator fuse / cube with a 200A version of the same thing?

I'm not sure that's a bright idea. Your Tail Relay is un-fused 'downstream' of the ALT fuse.

Unless I'm missing something, I'd think you'd be better off backing up and wiring things the way you've now learned is the recommended way.

flatboy · 10-27-2012, 01:03 PM

I ran a big power wire, fused from my battery to this box in the back. It feeds my w/a pump, nitrous solinoids, heater, ect, my meth kit. Not sure if this idea would work for you or not.

Chris D. · 10-27-2012, 01:27 PM

What is an 3RZ-T?

Do you mean 3RZ-FE Turbo?

LTtaco · 10-27-2012, 09:17 PM

Thanks for the feedback.
I like that electrical box setup, it looks heavy duty.
I'm in the process of wiring it back to stock now and running the 0-gauge with a 230 amp inline fuse straight from the alternator to the positive post.

I did mean 3RZ-FE turbo.

LTtaco · 10-28-2012, 05:39 PM

Ok, so I fixed the wiring back to stock condition and ran my 0-gauge wire with inline fuse straight up to the positive battery terminal. I started it up and the battery light was on. I checked all my connections and all appeared well. I drove the truck around a little bit and shut it off. I went inside and grabbed my laptop to connect with my Halltech to see how the voltage was looking. With the truck not running and keyed on it showed 12V then I started it and it was showing 14.4V so it was charging correctly, when I looked over from the computer to the dash the battery light was off this time....Next I went for another drive and it was fine for a few minutes then when shifting through the gears I saw the light flicker for a second a couple times then it came back on again, so I pulled over and shut the truck off and started it again and the light still remained on. Next I drove it back the house, and shut it off again, let it sit for a few minutes while I ate lunch, then went back out and fired it up, no battery light. I have no idea what's going on with it. Any suggestions? Does the ECU control the signal from the 3-wire plug going to the alternator? Thanks for your help.

Quote:

Originally Posted by Enola Gaia

I'm not sure what you're doing ...

Are you wanting to replace the OEM 120A Alternator fuse / cube with a 200A version of the same thing?

I'm not sure that's a bright idea. Your Tail Relay is un-fused 'downstream' of the ALT fuse.

Unless I'm missing something, I'd think you'd be better off backing up and wiring things the way you've now learned is the recommended way.

Enola Gaia · 10-29-2012, 05:47 AM

Here (attached) is the 2004 charging circuit wiring diagram. The battery / charging indicator lamp should only come on when its circuit is grounded out, and in the OEM setup this occurs through the regulator incorporated within the generator itself.

First thing to check is whether the generator is grounding correctly / adequately.

Second thing would be to see if the wiring from the charge warning lamp is somehow grounding out intermittently (in an unexpected or incorrect way).

LTtaco · 11-01-2012, 03:13 PM

I checked all my grounds that I could remember, all appreared to be good. I unplugged the 3-wire plug from the alternator and did a voltage test on it. The two wires on the outsides of the plug metered 11.4v and the other 11.9v, the middle wire showed nothing, so I did an impedance test on it thinking it might be a ground and it still showed nothing. My gut is telling me this is the problem. I'm not too handy reading these schematics, so where would I check for a ground connection for that middle wire of the alternator plug?
Also, I started the truck and let it idle, then unplugged the 3-wire plug and the battery light went out, but it wasn't charging, as soon as I plugged it back in the light came back on, and of course wasn't charging.

Thanks for your help.

Enola Gaia · 11-01-2012, 03:25 PM

What color OEM wire ties into the 'dead' third wire on your alternator plug? The red and white OEM wires are coming directly from fuses, so they should be 'hot'.

The yellow wire (the one I suspect is 'dead') is the line from the charging indicator lamp in the dash. This wire comes *from* the charge warning lamp to the alternator. It's supposed to ground through the generator itself (presumably the generator mount).

Does the charge warning lamp (dash) go out when you disconnect the 3-plug connector? It should.

LTtaco · 11-01-2012, 05:49 PM

Quote:

Originally Posted by Enola Gaia

What color OEM wire ties into the 'dead' third wire on your alternator plug? The red and white OEM wires are coming directly from fuses, so they should be 'hot'.

The yellow wire (the one I suspect is 'dead') is the line from the charging indicator lamp in the dash. This wire comes *from* the charge warning lamp to the alternator. It's supposed to ground through the generator itself (presumably the generator mount).

Does the charge warning lamp (dash) go out when you disconnect the 3-plug connector? It should.

Enola, I won't be around the truck until tomorrow to check the color of the said wire. When I disconnect the 3-wire plug the dash light does go out. I'll report back with my findings ASAP.
I really appreciate your help.