I have a 2004 Civic Ex, which I purchased used a few months ago with 43k miles. The car runs well and gets good gas mileage, however, it seems to have a very consistent habit of flickering lights at idle once the engine is on. In fact, it seems there is a voltage pulse in the entire system. The dash lights, headlights, cruise control light and dome lights all pulsate in intensity with the idle of the engine. At start up, you can even hear the pulse in the power windows when you roll one down.

I took the car to a local AutoZone to have the battery and alternator checked. The dude that checked the car said the alternator and battery were fine. Under load (2000 RPM), he said the alternator was charging in the 14V region. He also said the battery was working fine.

I've never had a problem starting the car or anything else. I just find it odd and annoying that the electrical system seems to have a hamster with a hitch in his getty'up.

Any ideas???

 

Upgrade the ground cables in the engine compartment.

 

Heyyy next time try searching, i had created a post about this, happend to my car last thursday. I had the air bag, ABS, brake light and other all flickering as well, i thought something was wrong with my brakes, so put it on a code reader and i got a low voltage code back, even though i had replaced my battery two weeks ago, My headlights would also flicker as well as your's do. It your regulator in your alternator, new cars come with internally regulated alternators, your's went bad just like mine did, the only way to fix the problem is have it rebuilt or replace it with a new one, new alts. for our cars run about $150 new, and rebuilding them should be around $80-$100. Just make sure you get it fixed quick before you start blowing light out and nuking your batter!!!!

 

I dig what you're saying, I too have suspected the "voltage regulator" in my alternator. However, I've had the alternator checked at both AutoZone and the Honda dealer. Both places told me that the alternator is working fine. Was that your experience too?

The alternator in this car was replaced with a PepBoys part about 3 months ago. Unfortunately, the previous owner replaced the alternator the same day I bought the car, so I'm not really sure what the car was doing before--losing charge on the battery, flickering lights, et cetera. As long as I've owned the car, the lights have flickered. But, make no mistake about it, the alternator is only 3 months old and the dealer and AutoZone say it works fine.

I wonder if the part is just faulty? It does make sense to me that the voltage is not being properly regulated at idle or else the lights wouldn't flicker. But, wouldn't the Voltmeter show that improper regulation? Or, is the Voltmeter not sensitive enough to pick up the subtle pulses that might cause my problem?

Full of Questions... Sorry. Thanks for your continued help.

 

Where the expletive is your volt meter???? i sure as hell dont have one in my civic ex!!! LOL. Well unfortunatley that your alternator was "replaced" the same day you bought the car, doesnt mean it was really replaced unless proof, like a reciept or something, and autozone will show your car while the voltmeter is hooked up while the car is running if the regulator is over or under charging the batter, you say you have flickering lights which is due to being over charged. When the lights flicker a quick shot of high voltage (more than 12V's) is running throught them, then they return to 12V's. this is what is making them flicker, trust me its a regulator problem. The regulator is located inside your alternator. Please go have another shop check it out before you nuke your batter, or even worse your ECU.

 

I was referring to the Voltmeter in the hoofs of the dude checking the charge on my battery...

I drove the car to the garage of the dealership with the new part in hand (bought at PepBoys) and watched the underpaid and overworked mechanic put it in. So, there is no doubt the alternator was in fact new and replaced. However, after closer inspection, I have a few more details to mention that may be of note to those more experienced than I...

At idle, the lights flicker without the AC on. Once the AC is turned on at idle, the lights play nice. At cruising speeds, AC on or off, the lights flicker. At idle, if the fan kicks on, the lights play nice. Once the fan kicks off, the lights start doing their thing again. So, based on those observations, it seems as if the problem subsides when the radiator fan is blowing (I think it automatically spins with the AC on).

More food for thought. Thanks for the continued feedback...

 

Heyyy the only reason your lights play nice with other accessories on is that when you have the AC or when the thermostate kicks in they draw more volt from the alternator, while your drawing more voltz from the alternator your lights play 'nice' while in fact they should dim quite a bit if your regulator is only putting out 12 Voltz. But hey if you dont want advice i wish you the best of luck than trying to prove other people's past experiences and knowledge wrong, i wish you the best of luck and hope you solve your problem.

 

If hes a mechanis at a dealership he is def not overworked and underpaid lol....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GIXXERMAN83 &raquo;</TD></TR><TR><TD CLASS="quote">Heyyy the only reason your lights play nice with other accessories on is that when you have the AC or when the thermostate kicks in they draw more volt from the alternator, while your drawing more voltz from the alternator your lights play 'nice' while in fact they should dim quite a bit if your regulator is only putting out 12 Voltz. But hey if you dont want advice i wish you the best of luck than trying to prove other people's past experiences and knowledge wrong, i wish you the best of luck and hope you solve your problem.</TD></TR></TABLE>

If his alternator is putting out 14v... than it's doing what it's supposed to be doing... but with these alternators to make sure everything is running like it is supposed to be you really have to test it yourself. It can be difficult to e-mechanic our alternators due to the many factors that go into the charging system.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thinknology &raquo;</TD></TR><TR><TD CLASS="quote">

If his alternator is putting out 14v... than it's doing what it's supposed to be doing... but with these alternators to make sure everything is running like it is supposed to be you really have to test it yourself. It can be difficult to e-mechanic our alternators due to the many factors that go into the charging system.</TD></TR></TABLE>

That is the point i was trying to convey, either his regulator **** the bed and is putting out too much or too little voltz

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GIXXERMAN83 &raquo;</TD></TR><TR><TD CLASS="quote">

That is the point i was trying to convey, either his regulator **** the bed and is putting out too much or too little voltz</TD></TR></TABLE>

But it doesn't necessarily HAVE to be his regulator... I don't completely understand his post. But if he has replaced the alternator with the same problem occurring... then something else is probably at fault.

 

The day I bought the car, the dealer told me it needed a new alternator. Skeptical, I personally drove the car to Goodyear and saw them test the battery and charging system. They found the alternator was faulty. Therefore, the dealer bought the part and I took the car that same day to the dealer's garage with the new part in hand. The mechanic put the part on. I drove approximately 250 miles back home from the dealership.

Almost immediately, I started to notice the strobe effect of the dome lights and the headlights in the early morning and night. I began to research this issue to see if anyone else had similar symptoms. I found, unfortunately, that the voltage regulator was an internal part to the alternator--you have to get both if only one is faulty. I suspected the voltage regulator from the beginning. But, I'm not a mechanic, and therefore, I chose to take it to both O'Riley's and AutoZone for free checks. Both gentlemen agreed the battery and alternator were behaving correctly. Still perplexed, I took the car to the Honda dealer for an oil change, and asked him to have his tech check the ground wires on the chassis and engine to see if that might explain the flickering lights. Fortunately, his electronic tech was standing there, and became interested in the problem and agreed to troubleshoot the whole thing for free while the oil change was being conducted. The tech came back and told me he couldn't find anything at all wrong with the grounds or charging system.

I am very concerned about this issue and understand what my car is doing isn't normal. However, I've taken the vehicle directly to the horses mouth with the dealership, and they don't seem to know what the heck is going on. You guys have mentioned this management unit that tells the voltage regulator how to charge the system with different loads. Is it possible that the alternator and voltage regulator are doing their job, while this management unit is failing to communicate correct information?

Thank you all for your continued help. I hope the above clears up the confusion from my earlier posts...

 

Ahhh yes, that is much clearer...

and yes there can be other problems with your charging system... here's some reading material for you so you can better understand... any questions just ask, I'll try to find the sites I used when diagnosing my alternator that were very helpful

http://findarticles.com/p/arti...66330

But I am still not sure as to what is causing said "flickering" but I wanted you to know that just because something is wrong with your electrical system or even if your car wasn't charging it's not ALWAYS the alternator's fault.


Now this site is the Honda Service Manual and if you don't have a fast internet connection... well it will make your computer blow up...

Page 4-21 has the wire chart to show you how this thing is hooked up and 4-22 through 4-25 give you some trouble shooting tips.

http://powweb.hondahookup.com/...l.pdf


Modified by thinknology at 3:05 PM 9/18/2007

 

Just thought I'd update y'all on the car... It's fixed--but not cheap.

Although the alternator was brand new and was charging enough to keep the battery in check, it was producing an inconsistent charge averaging on the high side of 14V rather than the factory spec lower end. Honda and two autoparts stores both agreed the alternator was working fine because it was charging over 14V. But, my mechanic decided the amplitude of the average was too sporadic and high for the car to be operating correctly. So, he decided to replace it (both the voltage regulator and the alternator parts).

But, instead of giving me the alternator to take back to PepBoys and get an exchange, he said they'd ultimately not honor it because of the tests they'd run. So, he just told me his advice was to have his guy rebuild it. So, in effect, between this alternator and the one I received three months ago, I'm out almost $500.

Yeah, that hurts. But, the upshot is that now my car runs even better than it did. I noticed that the transmission would sometimes get confused at low speeds before between overdrive and a lower gear. However, now it doesn't. The power surges were causing my transmission to shift incorrectly as well--something I didn't aptly realize. Anyway, the $319 bill for the alternator hurt me pretty bad today, but all in all, I suppose it is worth it in the long run...

Out.

PS--For those of you who are making a grimace right now about that bill, believe me, I'm embarrassed too. I'm surprised the mechanic had a straight face when he gave me the bill. He kept the car for a full week, and upon just wanting to fix the voltage regulator, I somehow get charged over $160 for the alternator alone--the rest for diagnosis and install. Something inside tells me he call no joy and went and bought the part at AutoZone himself. Oh well, maybe I did get screwed, but my car is running alright now.

 

Thats what i had been telling you all along bro, and you should have not payed more than 100 dollars to get the alt. rebuilt, because a brand new alternator for our cars is only 147 at autozone!!!!