Rep Power: 0

So for the last couple of weeks I've been having issues with my 04 civic ex. 2 weeks ago I was heading to work and when I went out the car wouldn't start, battery was dead. I for a jump start and got to work; this was a 30 min drive. Again, when it was time to leave it wouldn't start but a guy at work gave me a lend of his battery jump kit so was able to make to the sister-in-laws house. This meant driving the car for 2 hours. I thought it was the battery but when I went out next morning (Saturday) to bring the battery to autozone to test it the car started no problem. Went there anyway and they said the battery was fine (they just measured the voltage as far as I know). While I was there I bought my own jump kit just as a backup.

Then Sunday evening when it was time to go home I had to jump start it again. I had to then use it Monday and Tuesday morning to start the car. Lucky only had 2 days work as it was Thanksgiving week. Got up to sister-in-laws house and next morning battery was dead again. We went to Squaw Valley for the Thanksgiving holidays (in their car) and when I came back on the Saturday evening I bought a battery in Autozone. I put it in Sunday morning and the car started fine every time until Wednesday morning, it needed a jump again.

So at work a friend and I went out and found out the car and put a multimeter in between the + battery post and the + battery cable and there was something drawing 3.5A even though the car was switched off! So we started pulling relays and fuses until the load went away. The current dropped to zero when I pulled the relay for the AC. Seems the relay was stuck on. I left the relay out and the car started fine.

However this morning coming to work, I had to have lights, fan, rear window de-fogger, wipers on etc as it was raining heavy and I noticed the wipers were a bit slow. Then when I stopped at traffic lights I noticed my lights were fading, the radio went off as if the car was switched off, the wipers could barely move, ABS warning light came on, and the spedo, rpm gauge fuel and temp gauge all switched off and then on. I increased the rpm of the car and it seemed to come back.

So this afternoon I went out and attached a multimeter across the battery. It was reading 11.6V. I got the car started, it was a little sluggish turning over. The voltage was then reading 14.3V. I started to switch on lights, radio, fan and de-fogger. With all these things on and the car running at 1000rpm the voltage dropped to 11.9V. Even when I ran the car at over 3000rpm it never went up to the normal 14v+

So is my conclusion correct? Is my alternator almost dead and what are the chances it will last another week?

I am planning on getting a re-conditioned alternator from Majestic Honda, the cheaper one listed.
http://www.hondaautomotiveparts.com/...8MITSUBISHI%29

 
Rep Power: 208

from what you have said, i think your alternator is fine,

your problem is elsewhere, where exactly i do not know,

try driving the car for about 30-60 mins.....stop the car and shut the engine off, wait 20 seconds and try to start the engine, does it start?

if it does, something is draining your battery while the car is sitting/shut off,

 
Rep Power: 517

The battery has to start the car, and that's it. The alternator provides the electricity to keep the car going once it is running.

If the alternator wasn't working at all, you would be stranded just minutes after getting a jump start.

I figured you have a battery dead, dying, or drained, for whatever reason. (Or bad connections.)

Until I got to this part: Is the belt tight on the alternator?

 
Rep Power: 0

As far as i can tell the belt is good and tight but i will check it in the morning.

There was the 3.5A being pulled before I removed the AC relay and as far as I know the there is nothing else current while it's off but i will check again in the morning.

My friends theory is that one of the diodes of the rectifier in the alternator is damaged/broken and there for would only be charging at 50% of its capacity at most.

Any further thoughts?

 
Rep Power: 0

Do you have an after market alarm, key-less entry or autostart system? Did you recently do anything to the electrical system, fog lights, HIDS stereo, speakers, etc?

Any recent body work to the car? Any work at all?

 
Rep Power: 0

Only recent work was an oil change & brake discs a few months ago.

I realized that I wrote about this mornings problem incorrectly. The lights, gauges etc came back after I turned off the rear defogger and fog lamps and increased the rpm but the abs light came on and off a few times for a couple of mins.

 
Rep Power: 517

That by itself could kill a fully charged battery in about a day.
It would kill a partially charged battery in much less time, depending on the battery condition and SOC.

But it should not kill the car while driving, the alternator can easily keep up with that small amount.

See what happens with the AC relay out of the picture?
Have the alt tested?
One diode bad would kill a percentage of the charging amps: 1/4, 1/3 etc., depending on the design of the alt. A VAT test should show if the charging rate is significantly lower than what the alt is rated at.

Poor connections or loose belt also limit the alternators ability to charge properly.

Doesn't your local Zone do these tests?

 
Rep Power: 0

The issue I had with lights etc happened after the relay was removed. I am going to go out and check belts now and also check for any pronounced AC ripple on the battery. I checked and the local autozone does do free alternator testing so going to go there too.

 
Rep Power: 208

take the alternator out of the car and bring it in, have them do a "bench test"

 
Rep Power: 0

I went to Autozone and had them do an alternator test while it was in the car, couldn't take it out or I'd have no way of getting to there. They said it all looks good.

On the way home I tried running as much electrical stuff as possible, lights, fog lights, defogger, fan on full, radio, wipers and rear defogger. Experienced no issues what so ever.

Is it possible that the battery was not fully charged on Friday morning since it only had 3 half hour drives before that? Going to put my battery on a charger tomorrow just to make sure its fully charged.