OK guys, long story here.

And yes, it's a 1G CRX question, but I just know there's some master techs out there that can answer this. I also cross-posted this on redpepperracing.com because I need answers fast!!

My friend has an '87 CRX HF that he got cheap and we just got done putting an Si longblock and tranny into it.

We can not get the stinking alternator to start charging!!!!

The car came with a bad alternator (bench tested bad) so we have never had the charging system working on this car.

*brand new battery
*brand new alternator
*Alternator has been re-tested at a local parts store and tests good on their bench
*both bat and alt are well grounded
*the main big wire (white) is properly connected, it's fuse is good, and it tests good
*the "IG" wire is getting 12v w/ the key on
*the "L" wire has been traced to the dash light and is properly connected
*the dash light comes on when the key is turned on, and stays on when engine is running

The only thing left is the third wire in the plug. labeled "S" (white w/ yellow)
We traced this wire to a black box under the dash, which after much research (going to the Honda dealer and bugging their guys) we found out is the "Alternator control box" which on HF models is used to shut off alternator in certain conditions to better fuel economy. OK, must be a bad box...


$300!!!!!!!

We don't need the fuel economy that bad!!!!

Honda says there's no way to test the box and their Electrical Troubleshooting manual is accually MISSING the pages that explain how the box works!! (not ripped out... they were never in there, the manual goes from page 44 to page 57)

We also found out from the local auto parts store that the p/n for the DX alt is the same as the HF. The DX doesn't have this control box, so where does that wire go on those?

We tried disconnecting the wht/ylw completely... nothing.
We tried connecting the wht/ylw to ground... nothing.
We tried connecting the wht/ylw to +12v... nothing.

Any ideas on how we can get this puppy charging????

 

Are you sure its not charging and the light is just staying on? Or are you basing that its not charging because the light is on? I'm no 1g expert but if the dx doesnt have this box but uses the same alt I'd think its charging but your box is just crap causing the light. Drive it around with the light on and see if it does actually die/kills the batt. If so start trying to find some junkers for that box. Stupid fuel economy....

 

It's accually not charging.

Took the alternator to a different parts store (car quest) and they did a more thorough check on it and found out that it is in fact bad!!! (see if I ever let Knect's test anything for me again!!!) Also, according to their computer, the DX and HF alternators are indeed different!!! Since my friend got this alternator off of eBay, he has no waranty on it and we're not even sure if it was a DX or HF to begin with, so a new, good HF alternator will be here tomorrow and hopefully all will be fine!!

 

Mabe it goes directly to the ECU on the DX.

http://b16a.honda-perf.org/wiringb16.htm