juror

Hello. Our 2005/177,000 mile Civic is once again showing signs of its age.

I was driving on the highway in slow traffic, and happened to notice that the ABS light came on. It turned off a bit later, then back on and off. Concurrently with this, the radio was cutting in and out. I glanced down as it came back on and saw that the display was going through its "I've just been turned on" routine.

I got off the highway earlier than planned upon seeing a sign for an unfamiliar route headed to the town I was going to anyway (this is not a part of the area I drive in often).

Having reached the safety of surface roads, where at least I wouldn't make the evening traffic report if the car decided to give up on me, I played around a little with the rear defroster and headlights, both of which had been on when the car started flaking out. At idle, I can reliably make the radio cut and the ABS light come on by turning them both on. So at least the problem can be reproduced.

Once I got home, I put a voltmeter across the battery terminals with the defroster and headlights on. I saw 9 +/- .75 volts. The headlights were also kind of flickering. I also heard clicking at one point. Opening the throttle raised the voltage maybe .5-1 volt, again with pretty big fluctuations.

Through all this, the battery not charging indicator did not come on. Also, no MIL, no SRS light, which I saw mentioned on a couple of threads about a voltage regulator going bad. Oh, and I don't have a code reader at my disposal to try to pull ABS codes :-/

So: Alternator? I've had one go on a '76 Triumph TR-6, and had largely similar symptoms. Kind of; the wiring diagram for the whole car fits on a singe page of the shop manual. And there's no radio, or ABS. It was more that an already temperamental car got a little quirkier.

Also, are the voltage fluctuations an indicator that the voltage regulator is screwed up too, or it the voltage too low for it to maintain a consistent voltage?

Thanks!

Slumpertcivic

juror

Boy, that'd be a real pisser if it was. We replaced the OEM battery a couple years ago with a cheapie from Autozone (we were still thinking we'd keep my car and sell my now-wife's Civic), and had it crap out on us (within warranty, woo!). When the original replacement crapped out, we upgraded to a less-cheap Autozone battery, which is hopefully still in warranty if that's the problem. Will report back once I get back from Autozone.

Thanks!

juror

At Autozone their test machine shows 11.91 volts at the battery terminals, which it reckons is 11% charged. No further testing is possible without charging the battery. I picked up an alternator under the logic that 11.91 is close to an even multiple of 2 and 6, and not 2 and 5, which I'd expect to see if a cell was shorted.

I'll put the alternator in tomorrow, drive it for a bit. By my thinking if the problem goes away, it was the alternator. If not, I can swap the alternator back and Autozone can replace the battery under warranty. Again.

Edited to add:

Please feel free to adjust my thinking if you think it's necessary :-)

ezone

Alternator stopped charging for whatever reason while it was being driven. Battery charge was depleted after alternator quit, it gave up all the power it could muster until systems shut down.
A good alternator can handle the loads as long as it's running and working. Test for alternator charging. Figure that out and fix it. (a blown fuse could make it quit charging, so it might not really be bad)

Charge up battery and make sure it passes tests.




Charge system warning light is sometimes meaningless. If the voltage regulator shot craps and that's what controls the warning light, you still gonna wait to see the warning light before you believe it's not working?

juror

The under-hood 80 amp battery fuse is OK. Ditto the 10 amp cabin fuse for the alternator. Now I'm trying to figure out how to get the darned wiring harness holder off of the bracket that's attached to the alternator.

I've said it before, and I'll say it again. This car was made for people with smaller hands to work on.

juror

Seriously?! The alternator pivot bolt doesn't come out? Even after removing the PS reservoir bracket?

Also, If I ever see that guy from the 1aauto.com videos on youtube at a bar, he is drinking on me for the evening. Never would've figured out where the tab was on that harness bracket without the video.

juror

New alternator is in and I have a consistent 13.9 volts at the battery terminals. Thank goodness. Now to get the mumblefrumble powersteering pump back in and we'll be back in business. And drop the old alternator at Autozone and get my core charge back.

To clarify, not that you all aren't awesome (and I'd happily buy several of you here a beer too), but that guy is always around and doesn't mind repeating himself a dozen times until I get it ;-)

juror

And the PS pump is back in. That lower bolt was obviously designed there by somebody who was supremely confident that they'd never have to loosen or tighten it while the engine was in the car. What a miserable job.

I'm not proud to admit it, but that bolt has had me as close as anything on any car to tears of frustration and rage. That said, I never had to change the plugs on the Impreza.

Alfie17

Glad the cars ok! i've had to replace my alternator twice and i always have a struggle with that wingnut... I had the Autozone alternator start whinning on me, im on my 2nd replacement and i can hear a whinning from the alternator (almost sounds like a bad bearing) hopefully yours is better! The OEM alternator never made that noise the duralast ones make.

juror

Yeah, I'm not a huge fan of Duralast parts, and I don't have high expectations for this one. I'm kind of hoping it lasts until we replace the car, hopefully next summer or the one after. Unfortunately, I was kind of stuck with wanting them to check the battery and replace it under warranty if it was bad. And the fact that it was 9:15 PM when I got time to run out. Good luck with yours!

I took the original alternator to Autozone and had them test it before I had them refund my core charge.

Wait for it...
...
...
...
It tested good.

FFFFFFFFfffrankincense!

I had them check the battery again. Their tester showed it at 60% charged. That and the voltmeter test strongly suggest that the battery is now charging.

So. False positive on their test or was there likely some other problem that taking it apart and putting it back together fixed? Like maybe a bad alternator ground or that 4-pin connector needed to be wiggled? Swap back and see if the problem reoccurs? It'll probably take less than 3 hours since I half know what I'm doing now... Do I even want to know how many hours the book says this takes?

I'm out for the weekend, but I'll check back on Monday. Thanks in advance for your thoughts.

Edited to add:

Sorry if I'm now firmly in the realm of stupid questions. My mental model of the charging system is insufficiently complete to ask smart ones :-P

At this point my take on the situation is thus:

With an assumed good alternator (the new one), "the rest of the charging system" has been proven good, meaning either:

1. The old alternator is bad, and "the rest of the charging system" has some nuance to it that Autozone's test doesn't test, and the positive test result is a false positive.
2. The old alternator is good, and some perturbation of the alternator connections has rendered the charging system functional again, independent of which alternator is in the car.

ezone

How many miles on it?

I've had many that wouldn't charge when they came in to the shop.......no noise at all.....but whack it with a hammer and it starts charging.
It's still a bad unit at that point, because it's gonna quit working again shortly

Slumpertcivic

juror

Mileage is closing in on 180,000, and I definitely gave it a couple of thumps with a dead-blow to get it to pivot down enough to remove the belt (after loosening the wing-bolt, obviously).

Great! That's two good reasons I don't have to take this apart again. Thank you both!

ezone

It moves much easier after you loosen the large upper mounting bolt

ezone

Somewhere earlier in this thread I wanted to say
In addition to a failing alternator making a loud howl or whine noise, you should also know that a good alternator that is charging at a high rate can also emit a pretty loud whine too

juror

That was after loosening the large upper mounting bolt; there was either an accumulation of schmutz (go ahead, name your next band that) or corrosion after 13 years and 180,000 miles. I cleaned the ears the alternator sits between with emery paper before putting in the new one, and it was still pretty tight. Getting the new one lined up to thread the bolt required yet more hammer taps and the use of a pry bar to pop it back out when I went to far.

ezone

That bushing in the bracket needed to move in order to give the alternator clearance. You can see the bushing near the head of the long bolt. It takes a little force to move, I usually just wiggle or pry the alt sideways and that's enough to push the bushing over.