I was driving from San Francisco, to San Clemente (Orange County, Ca) which is about an 8 hour drive and I was going about 85-90mph most the way on the freeway(the speed of traffic) and after I went over the grapevine, which is a big hill, my batter light came on in my 91 Civic Si, so I turned off my CD player, fog lights, and radar detector because I didn't know what else to do, and after about a half hour my headlights were so dim I couldn't see in front of me, my clock was dim, and my winshield wipers were going really slow(it was raining at the time). So after about an hour, I had to pull off the freeway because I couldn't see in front of me, my tach went crazy then went to 0 rpms, my check engine light came on and the car was bogging, I assume there was no batter power for a good spark. So when I stopped I didn't turn off the car because I knew it wouldn't start again and I let it idle for about 10 minutes. Then I hear a CLICK and the idle went down a bit, as if you turn on the A/C, and and I could see my clock again and my tach started to work again, and the batter light turned off. So the headlights came back on then I was on my way again, and it was fine the rest of the trip. So I have no idea what was wrong. I don't know much about these cars because I just got it two weeks ago, but I think either the rain shorted out something on the altenator, or maybe the altenator got too hot and shut off? I really have no idea, so I don't know if I need a new altenator, or just let it be and hope it doesn't happen again. Any help would be great because I have to go back to San Francisco and I don't like knowing that something could go wrong at any time. Thanks!
Oh, the car is stock except for a dinan chip, which has been in there since 1994.

 

I had the same problem and it was the altenator. Go and get it checked.

 

Definitely get the alternator and battery LOAD tested. Sounds like you need a new alternator. You also want to check and replace the battery cables if there is any corrosion on them or the terminals are not of the permanent/molded type. I even went as far as to replace the valve cover to core support ground wire.
Something few understand is that the alternator is controlled by a signal from the ECU and that there is a device in the main fuse panel (underhood) called the ELD. Check all of this stuff using the Helm or at a dealership if the problem persists.

Why do I know-because it happened to me a long time ago just like yours and indeed the generator (that long ago) quit.

Safe travels and happy holidays

 

Greay, thanks alot. I'll definetely get the altenator/batter checked out. Happy holidays to you guys too.

 

my problem is similar to yours, except my battery light went off, but sometimes comes back on, but i also had those same symptoms, and so far i replaced both battery cables, checked my alternator ground wire (running from underhood fuse box to alt), i had my battery and alt test good, but now my battery light still comes on, but the car starts fine and runs, but i don't know if this is going to happen again.

but, you can read my original post here, it explains more detail, and some of the replies might be usefull to you: https://honda-tech.com/zerothread?id=358286

 

make sure the battery is good, alt is good, the battery cables are good and clean, and all the grounds are good, and the #14 fuse in your dash fusebox is good, your alt belt the correct tightness, make sure the wire plug (green), is not dirty and that it is connected tightly to alt, make sure grounds have clean connection, have alt tested a few times under different conditions just to make sure, cause i had mine tested a second time and the second time, the guy said its possible it is a bad wire going to the alt, but i am still trying to find my problem out also, so good luck