Dying battery/alternator/both ????

I have such a pain in the ass. My friggin honda has a problem losing battery power. It runs fine with no load on the system. A voltmeter shows about 14.? Volts and will stay there until I turn on the lights or the heat or step on the brake. If I turn on the lights or the heat the voltage drops very quick from the 14+ volts down to 13.88, 13.7, 13.0, etc. until it is in the low 12s. If I drive at night or in the rain and need the lights or wipers, I eventually have to pull over because the lights go too dim to see, the battery dies and I get nothing from the wipers, power windows, radio, lights, horn, heater fan, whatever. I had another old battery that I charged and swapped in place and after a couple of days, the same thing. So, I thought well, it has to be the alternator, right? Swapped that out too. Same friggin thing. I spoke to a few people who said, "Its gotta be a bad ground". Well, if it is, I can't find the friggin thing. I swapped out the negative battery cable and replaced the terminal on the positive cable too. This cheap ass manual that I have says that there is an Alternator Control Unit under the left side of the instrument panel. I looked and didn't see it. I've never heard of one either. To me it sounds like the voltage regulator is the problem but, on two alternators? Both alternators, both batteries, same friggin thing. What the ....?

There are three grounds, One from the Batt. to the body, One from the Thermostat Housing to your Wiring harness, and one from the block to the rad. support. Might want to make sure your connections on the Alt. are in good condition too.

Bring your car to Autozone, Advance Auto, or most any major autoparts store. They can check your charging/battery system in the car. I suspect you got a bad replacement alternator. Was it was a rebuilt unit? BTW, the voltage regulator is in the alternator. GL

i believe it's a bad ground, because my car does the same thing!

i'm bringin it to autozone this week and havin em check it out :)

If it was a bad ground I think the lights would just kinda blink. When I did my b16 swap I had a bad ground and it just made the lights go dim and then come back but they never got so dim that I couldn't drive. What happens when you run the stereo?

It could also quite possibly be a bad ecu not sending the signal for the alternator to charge. It's rare, but it does happen every now and then. I'm not sure how to check and see if it is doing that, but it's an option if you've done everything else. But first, take your car in and have it checked out and see if they can find anything.

First off, thanks for the replies so far. To answer your questions, the alt came from the same honda parts place that I got the original from less than a year ago. It was pulled off a car that was scrapped. I checked the grounds that go from the negative battery post then to the body then to the tranny bolt. Also the one that goes from the valve cover to the frame at the radiator. I didnt see one on the thermostat housing yester but I am going out to check on that now. If that isn't a problem then I am making the 1/2 hour trip to Autozone to get the thing checked out. As far as the Sterio goes, I just have a simple stock type setup. Nothing fancy at all.

I just want to shoot this piece of crap and I wish it would just catch on fire to burn to the ground. Then I could just get something else to spend lots of money I don't have and spend every friggin weekend fixing and loosing work because of a piece of garbage that I am learning to hate more and more every friggin day. What in the hell? Can you tell that I am BITTER and PISSED OFF? Both the old alternator and a brand new one that I got today from a very reputable shop do the same thing (not an AutoZone, or Checker, replace it every other month, like you have nothing better to do than check out their stock of crap parts when you finally get one that works and return the other 3 or 4 that just keep getting recirculated back on the shelf ). When cool, both the alts put out about 14+ volts, for about 5 minutes. When I turn on the lights and the heater fan to high, the volts drop and then come back upfairly quick. Then after about 5 minutes, the volts will go down quicker than Monica in the Oval Office. The rpms go down from about 950 to maybe 600. If anything, shouldn't they go up? I did this same test on my wife's car. I can turn every friggin thing the car has to high and the volt meter doesn't move, the idle speed doesn't change, nothing changes and it all works great. There is an (according to the cheap ass manual that I have ) "electric load detector" in the fuse box mounted on the passenger side close to the firewall. It has 3 or 4 wires in one of the connectors that then go to the ECM. Does anyone know how to test that or what the thing is supposed to do once it detects an electric load? There is no ground wire going from the thermostat housing to anywhere. There are no wires on the housing at all. The car is an 89 Civic LX, 1500 with a manual tranny. Does anyone else have any ideas? I need this heap to run quick so I can go to work and make some money instead of wasting it on parts and loosing time off from work.

Try taking it to a honda shop and see if they can test the ecu and see if the ecu is causing the problem. A friend of mine here locally had the ecu go out and stop telling the distributor to charge.

Click this link for the ELD (Electric Load Detector) test... http://www.binghamtonlife.com/manual/2gsm/images/91-23-71.jpg

These are the important Ground locations... http://www.binghamtonlife.com/manual/2gsm/images/91-23-9.jpg

For manual click here... (for 91 crx but almost everything dx is the same)... http://www.binghamtonlife.com/manual/2gsm/default.htm

And if your alternators keep tearing up, go to a place that only does alternators.

GL

OK here we go with another update. I got a new alt yesterday. Same problem. I tested the ELD which is in the main fuse box. It tested ok. I took every fuse out of the fuse box in the car under the dash 1 at a time and tested the voltage with the engine running right at the alternator post to frame ground. With the headlights, and/or the heater fan motor on, the voltage drops immediately to the low 13s then continues to go below 12V if I don't shut off the lights and/or heater. Anyone want to tackle this one?

CHECK THE GOD DAMN ECU - if it isn't sending the signal to charge, or is intermittent about it - you'll get voltage drops with all those devices on. Either that or you've got a short on one of your devices. Do you have a friend with the same ecu you've got, try swapping it.

CHECK THE GOD DAMN ECU - if it isn't sending the signal to charge, or is intermittent about it - you'll get voltage drops with all those devices on. Either that or you've got a short on one of your devices. Do you have a friend with the same ecu you've got, try swapping it.

How do I check it? What is the signal voltage supposed to be? Which pins on the ECU do I connect to? I don't know anyone else with an 89 Civic, or any year 4th gen.

Don't know, prolly have to take it to a shop that can test it. Thats what my friend had to do after he replaced all the same stuff you did.

What solved his problem?

Also, I have an appointment scheduled for Friday morning with a honda dealer. $84 / per hour. If you can find out what solved your buds problem 4G4D, it may save me some hard earned cash.

Well, I went to the dealer on Friday last week. They had it for a few hours and said that the alternator was the problem. I explained all that had been done by me and they said that they had done all the same things I had done. So...... I got an alternator from someone who has a good running honda just like mine. Guess what ? Same stinkin problem. I got another ELD (built in to the fusebox under the hood on the passenger fender) as a whole unit with the fusebox, and the main fusebox under the dash below the steering column. I changed out the ELD/Fusebox under the hood and tested it. Immediately after starting the car, the voltage was at 12.6 volts (it should be up over 14V.) and the idle was going up and down, up and down, for about 2 minutes. I then hit the power window switch for the driver window and the voltage went up over 14V. I turned the brights on and the volts dropped and immediately started to recover to the 14+ Volts. I shut the lights off and waited for the engine to warm up. After about 5 minutes the fans came on and I went to turn the lights on. After turning on the lights ( brights ) the volts dropped like a rock and continued until I shut them off. I then turned off the car and replaced the main fusebox under the dash below the steering column and started the process again. this time the car seemed to do better but didn't recover with the brights on. If I just had the low beams on the voltage actually held around 13.6 to 13.7 Volts. The RPMs still drop and do not come back up until turning off the lights. If I manually hold the throttle to increase the RPMs then the volts go back up. Tomorrow I will put my original ELD back and try that. If anyone has any ideas please let me know.

I got a ECU for ya $40 shipped if you want it. Its a cheap test and if its not the problem off it on ebay for $40 and make your money back. let me know if ya want it..