Performing the "Big 3" Wiring Ugrade on a 3rd Gen T4R - A How To

So with all these upgrades ya'll are doing, maybe someone can help me. I'm looking for an electrical schematic for a 1997 4Runner 3.4L. Specifically the charging system and Battery Light. I'm in another thread for Alternator light on, but voltage is good everywhere I have checked. She starts and runs perfectly. Any input is greatly appreciated.

Here you go:
 

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Here you go:

You sir, are stupendous!
Help me interpret this please? Looks like power is coming in from the 7.5A fuse, thru the charge light, and returning to the alternator? Is the alternator misinterpreting what is returning? or could something before the fuse be my problem? Fuse is fine, do you have a schematic for whats before the fuse (From Power Source System, Page 58)?
 
You sir, are stupendous!
Help me interpret this please? Looks like power is coming in from the 7.5A fuse, thru the charge light, and returning to the alternator? Is the alternator misinterpreting what is returning? or could something before the fuse be my problem? Fuse is fine, do you have a schematic for whats before the fuse (From Power Source System, Page 58)?

If your problem is the light is staying on, then the fuse and upstream of it are obviously not the problem. If all connections to the alt are good, and the alt is charging normally, then the section of the IC regulator that cuts ground to the indicator may be fried.

So either swap out the regulator or just live with the light.
 
If your problem is the light is staying on, then the fuse and upstream of it are obviously not the problem. If all connections to the alt are good, and the alt is charging normally, then the section of the IC regulator that cuts ground to the indicator may be fried.

So either swap out the regulator or just live with the light.

Answers, I love answers! I may or may not have a warranty on this alternator. Will have to contact previous owner. If this is the case, how can I prove it is faulty? Any tests I can show definitive results for?
 
Answers, I love answers! I may or may not have a warranty on this alternator. Will have to contact previous owner. If this is the case, how can I prove it is faulty? Any tests I can show definitive results for?

Well, there is the obvious of testing with another alt.

Presumably you can show continuity to ground on the L terminal with a test light while the engine is running. Connect your probe to the positive battery terminal and the other to the L terminal of the alt and see if the test light goes on. If that happens, either the alt is not charging, or the IC regulator is faulty. Either way it is defective. I don't think there is any static test you can do. Have to spin it to test it.
 
Nice write up. I have few questions. Why you have 4 wires if it's the big "3" upgrade ? Im guessing your 4th wire was from negative battery terminal to engine ? Why?

I only currently upgraded my ground wire from battery negative to chassis. Using a really really thick 2 gauge.

And I'd like to upgrade the other wires. I personally don't think it's good to crimp down on a solder connection. Your breaking the solder up inside the connector.
 
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Well, there is the obvious of testing with another alt.

Presumably you can show continuity to ground on the L terminal with a test light while the engine is running. Connect your probe to the positive battery terminal and the other to the L terminal of the alt and see if the test light goes on. If that happens, either the alt is not charging, or the IC regulator is faulty. Either way it is defective. I don't think there is any static test you can do. Have to spin it to test it.
So, I caved and replaced the alternator and guess what?! The damn light is still on! Where and how many ground cables are there? I'm gonna pull all of them off and clean em up. I got the obvious one on the drivers side fender next to the battery.

Sent from my SM-G930U using Tapatalk
 
where are the pictures this thread is useless without them...

Send me $40 via paypal so I can pay photobucket their extortion fee for the month, and I'll have them right up for you.

Otherwise, quit with the self entitled complaining. I figured it out on my own and so can you. The pictures will be restored when I have the time, until then you'll have to do without the spoon feeding.
 
The pictures in this write-up have all been restored. Big thanks go out to [MENTION=65101]BrianSD_42[/MENTION] for re-hosting the pics, and to [MENTION=84643]JBurt[/MENTION] for his willingness to help out as well.
 
Solder only or crimp and solder?

Great writeup BFAD!

Regarding the solder strength question, there is just one phrase to keep in mind: solder bonds are strong, bulk solder is weak. Take a piece of solder wire and bend it or pull it until it breaks, and you'll see what I mean. So if it were me, I'd keep the solder joint thin by crimping then soldering, not because the crimp will hold it together, but because the thin solder joint will!
 
I did this a few years ago (it's also popular on 2nd Gens with great results) and it gives me the peace of mind running a bumpin' stereo, extra lighting, 2nd fuel pump etc. I have more consistent voltage now, and with the stock alternator still.
 
So, I caved and replaced the alternator and guess what?! The damn light is still on! Where and how many ground cables are there? I'm gonna pull all of them off and clean em up. I got the obvious one on the drivers side fender next to the battery.

Sent from my SM-G930U using Tapatalk

By any chance did you or the previous owner swap any dash gauge bulbs inside the cluster? I ask because I had some odd goings' on similar to your situation with a light that would not go off when it should and not come me on when it should. Can't recall exactly what the issue was but I remember having to fiddle with or replace the bulb itself. Made no sense to me at the time – but it worked whatever I did.
 
I'm about to do the upgrade and was wondering the same thing
Did you ever get an answer?

-B

I'm about to do my big 3 and need to know what size lugs to buy. Are most of the bolts 5/16", 3/8" or a mix? If they are a mix then I'll just drill the 5/16" lugs to make them fit.
 
Does anyone make just the wiring kit? Not so good with all the soldering, so if I can get the cables made...I could just get it all straightened out myself. Thanks.
 
Does anyone make just the wiring kit? Not so good with all the soldering, so if I can get the cables made...I could just get it all straightened out myself. Thanks.

The soldering is actually pretty easy. All you need is some solder, a vice or pair of vicegrips and a cheap butane torch from Home Depot. I found it much easier than soldering little 20 AWG wires since it's not detailed work, just heat it up, stick the wires in and then let it cool and it's rock solid.

I know there was someone selling kits for 2nd Gens for a while, but I have not seen any for sale for 3rd Gens.
 

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