What fog bulbs are you running?

 

My lights flickering/wavering started in 2011. I had the battery replaced 11/11 and it got better. Then started again during this past winter 2012. Had battery checked and it was bad 2/2013 (now I know that a bad alternator can ruin a good battery) and it was bad again so it was replaced under warranty. During this time not only was my lights flickering but my engine was wavering whether my heater was running or not and when the heater fan was on it was wavering. The battery replacement this time did not help. This did not happen all the time but was happening just about every day. Even though Honda could not shed any light on this problem or its cause, mechanics were suggesting the diodes gone bad in the alternator. Last week I went ahead and had the alternator rebuilt and sure enough 2 of the 6 diodes in there were gone. Now I am very happy to say that I have had no more flickering or wavering of lights fans or engine. Yeah.
Lori

 

Just as a note. A DMM cannot read fast enough to show a voltage chaning that quickly. You need a true analog meter to see fluctuations that are that fast.

That said, it's definetly something in the chargeing/regulation circuit. I doubt it's the same thing that my civic did, but it may be worth checking. It did a similar thing but slower, and was blowing the fuse for the battery charge circuit, turned out to be the wireing loom shorting out against the intake manifold.

 

I once had a large computer that had random errors that went on for several months. After many, many service calls for random errors, I decided this had to be a power fluctuation problem. The service company tech brought in 3 recording voltmeter and monitored all three phases of the incoming power for about 2 weeks. He saw nothing. The power source was 208 or 230 volt three phase. I forget which it was. That 208 three phase fed an internal 3 phase transformer that dropped the voltage to various secondary levels for the internal DC supplies. I finally bought in an oscilloscope and in 5 minutes the problem became readily apparent. One of the 6 secondary leads from the transformer was open. This was one of the 6 leads feeding the six diodes. It had the same effect as you a blown diodes.

The point of all of this is that a VOM either digital or a swing needle type is not fast enough to see this type a failure. On commercial power (60 cycle) there are 360 pulses per second on the DC side. Missing 1/6th of them is very difficult to see.

An automotive alternator works in similar way. It is a 3 phase AC device with 6 diodes. The frequency is not stable at 60 (or 50 cycles) but instead changes with engine speed. A digital meter does not sample fast enough to see these variations. A meter with a swinging needle might see it at slow engine speeds. The correct item to look for this problem is an oscilloscope. Put a scope on the +12 volt side and crank up the gain. You will be able to see the output of all 6 diodes and immediately be able to see any missing pulses in less than 5 minutes.

Congratulations on finding your problem.

 

Well, it is going back to the shop on Monday. Putting a new alternator in. Something Honda should have just done while it was under warranty.

 

If they will stick a scope on it they can see the problem of blown diodes immediately. It will not take them 5 minutes. If they are going to warranty the alternator then take the new alternator.

If the alternator does not fix it, then look at the at ELD as possibly the problem.

 

$650 out of pocket and a new alternator in.

Car is running great.
No more hesitation.
No flickering lights.
But..still have a little static on the radio when I turn on the headlamps. Need to get that sorted.


Underhood voltage reader/stabilizer (Pivot Mega Raizin ebay special) shows the voltage staying within tolerances now. Before, the alternator's voltage regulator was malfunctioning and the voltmeter was showing a 11.5-17v range....Now the voltage is staying around 12.4-12.7 when engine off and 13.5-14.2 when engine on. (with-in the acceptable range I believe)

 

Great. I'm happy you fixed it.

 

did you replace your alternator and if so did it cure the problem? I have the exact same issue, installed a remanufactured alternator that wouldn't even charge although it and the old one tested fine on the bench. Put the old alternator back in and now wondering if it could be the electronic load detector.

 

Glad you fixed it.

The earlier posts were right about the digtal volt meter. A scope or analog meter is the way to go for this kind of testing. Many shops dont even have an analog volt meter.

Many techs today rely on automated charging system test equipment which generally wont detect your problem. Much of the modern test equipment, especially the hand held charging system testers, "simulate" a load and dont have the ability to test as well as a good old fashioned carbon pile tester that has a dial which can be turned up to draw a huge load to check alternator output.

 

Yeah, if anyone has a similar problem and you are under warranty. REQUEST a an analog scope. The automated device is not effective for diagnosing this problem apparently.

The new (remanufactured Honda) alternator is working great. As I said, the old alternator killed the battery due to overcharging. So I did have to replace that as well. But it's been 6 months or so and it's running great. taking it in tomorrow to finally get the valve clearance checked and the manual transmission flushed and changed...and snow tires put on!

 

I know this is really old, but I at that time was running factory bulbs with the glass tinted with Duplicolor Metalcast yellow tint.

 

Any update to this issue?

I've been battling the same problem. I've had some intermittent problems but I'm hesitant to buy an alternator. I really wish I could squeeze my hands in there to troubleshoot without taking it out (again). I took it out and had it tested. The guy said my alternator was solid. It's so frustrating! I put it back in and everything was fine for a few weeks, but now it's completely bad. Arg. I don't like replacing things blindly... I'd rather know what the problem is first.

 

It worked fine for a few weeks after you put it back in? Check grounds, clean, replace hardware, check wires?

 

Yeah I did that. The grounds to the engine and frame had some corrosion. I feel it's a bad connection but I'm not sure where it is. I'm thinking it's at the alternator connection. I'll try again and focus a bit more on the connector. I might disassemble it and use solder.

I checked the voltage directly out of the alternator and it's only 12 (battery voltage). I'm assuming the 4-wire connector has some control of the output... if there's a bad connection at the 4-wire connector, the main output will be off. I'm not sure how to properly "pin-out" the connector when testing it.

I'll keep ya'll informed.


Does anybody know if the alternator has soldered connections on the inside?

 

I dicked around with it for two years before I finally replaced it...just replace it. I can't find a decent shop who can diagnose anything anymore...

The alternator IS going to test fine. It's the voltage regulator that's faulty ...but on our alternators it's all integrated. SO you have to replace the whole unit.

Solved my woes....

 

You might stop by a local rebuilder and ask if he can get you a regulator and install it in your alternator.

I once had an Prestolite starter quit on my airplane. I needed to be in Reno in two days followed by LA a few days later. A rebuilt starter was $400 plus shipping. The rebuilder said. "I have everything in stock. I'll fix it tonight, you can pick it up in the morning." His last question was "do you want it painted?" I said "no". He said pick it up after 8AM. I installed it and was off the ground at 10AM.

My point is who would have expected anyone locally to stock Prestolite parts.

Ask a local rebuilder.

 

Interesting, why does the failing vreg not show up in the alternator test?

 

So.....did you ever get your flickering lights issue resoloved? If so, what was the fix? I'm wandering if the replacement lowbeam switch replacement that was part of a recall was replaced with a nother faulty switch. I have the exact same problem as you've identified in your videos. The alternator tested good on a bench test, I inspected and cleaned all grounds and re-seated all fuses but the problem has not gone away. I have 103,000 miles on it. One of the guys at NAPA suggested that an 80 amp alternator is way undersized for a car with electric power steering and with that many miles the amperage is going to cvontinue to decrease over time with more wear and tear.

Any help or suggestions are welcome as I dread taking it to the dealer and having them diagnose the problem at their hourly rate.

Thanks,

Ken

 

Hey Lori,

I'm having the same flickering problem. How many miles did you have on the alternator before the rebuild?

Thanks,

Ken