SR20 alternator charging issue

[old510ballz]

Looking for a little help figuring out my charging issue. The alternator checks out good on the bench test, but isnt charging. Guessing its some kind of ground issue, but thats as far as my electrical intelligence stretches. The pictures are how the car was wired from DGR so im not sure whats going on. The two large red wires at the alternator attaches to the white/red stripe and white/yellow stripe stock harness wires and the small white/red stripe wire coming from alternator plug is going to red stock harness wire.

Any help would be appreciated

[datzenmike]

I used this diagram when swapping in a KA alt into my 710... worked perfectly.



The KA (or SR) plug has two wires. The thinner one is to be connected to the White/Red wire on the stock plug... this is for the red CHARGE warning light in the dash. The thicker one goes to the White wire in the diagram which eventually finds it's way to the + positive battery terminal.

The only thing left is the output from the alternator. I soldered a round lug on a piece of 12 gauge wire and bolted to the same terminal on the starter as the positive cable from the battery. The KS/SR output is almost twice the stock so running a thicker gauge wire seemed sensible. Oh, and a good ground connection to the alt. housing with the stock black ground wire.

[spoolinitup33]

Is you SR a S13, 14, or 15? On mine, the colors coming off of that plug that goes into the alternator are white (thicker wire) and white/red (thinner wire). All you need to do is take that thicker wire and put it to your battery, or if you have your battery remote mounted you can just put it to wherever you have your battery cable coming to, which I figure is the lug on your starter. The smaller wire, which, like I said, on mine it's white/red, you can put it to your charge light bulb or you can run it through a resistor. This is the one I used: http://www.radioshack.com/product/index ... Id=2062293

All you do is come off your fuse box with +12V and solder it to one side of the resistor, then solder the smaller wire from your alternator to the other side of the resistor. If you're not sure about DGR's wiring, I'd just do it the way I've said, it's easy to do.

[old510ballz]

I know this has been battered before, but I wanted to post pictures of my exact problem, so thanks for the help guys. I took the harness apart to check the wire order and all was good. I fussed with everything for a few hours and nothing worked. At the very end I messed with the alternator plug and whala. I have a new problem after getting working, its now charging at 15.2 volts. The sense wire (yellow) is hooked from the plug right back to the positive pole. The W/R wire runs to the low voltage light wire in the stock harness but its not connected to anything because of the aftermarket gauges. Not sure whats up.

[msaunders]

You need to connect the white/red wire up to either a resistor, or put the stock charge warning light back in. The alternator needs a load off this wire to start producing voltage at idle RPM.

[spoolinitup33]

X2, you need to hook that up.

[old510ballz]

You need to connect the white/red wire up to either a resistor, or put the stock charge warning light back in. The alternator needs a load off this wire to start producing voltage at idle RPM.

Can I just grab a radio shack light and connect the wire to that
I did plug a junkyard scrap dash in to see if it made a difference, but it is extremely thrashed!

Thanks for the help

[msaunders]

You could, but the easiest way is to follow what 'spoolin said with the resistor.. pick one up and wire it up between +12v and the w/r wire.

[old510ballz]

"Just wanted to say thanks to all. I went with "spoolinitups" recommendation and it worked like a champ. Charging at 14.2