My alternator was going out(the dash brake/battery light combo) so i replaced it. I replaced it with a reman. from autozone but i still got the warning lights for a few seconds each time i started the car. then i noticed that the dash lights where pulsing(getting dimmer then brighter in a rhythmic pattern) and the battery light would randomly come on while driving. someone posted a thread with similar symptoms and it was suggested that it was a bad voltage regulator. so the question is, do you guys think that i got a bad alternator. if so any advice how to proceed. the guy at autozone said they can't test it on the car so i would have to go to the trouble of taking back out and bring it in to be bench tested. i'm pissed. could it be something else i haven't thought of?

 

They can't test it on the car? wtf? I had mine tested on the car back in march at either advance auto or autozone (can't remember which).

 

They usually can only test voltage while it's on the vehicle, and can test with a load when it is off.

 

yeah, i can test the voltage myself. if its the voltage regulator i don't know what i would be looking for on my voltmeter. i guess maybe a fluctuation? thats what i seems like with the lights pulsing...

 

anybody have any experience with a new alty being defective? i really don't want to have to take it back out...

 

bump... so i was hoping someone would come through with a suggestion of what was causing the pulsing other than a faulty volt reg. i am really pissed that a new(rebuilt) alty would be bad. in a perfect world autozone would exchange it and give me half the cost back for my trouble but that is wishful thinking.

 

Well, have you had a load test done on the battery? Check all cables and make sure they aren't damaged. And yes, I have seen "remanu" alts bad right out of the box.

 

well i checked the voltage with the car running and it was fluxing between 14.5v and 15.5v which i already knew from seeing the pulsing of the dash lights. so i guess i will have a stiff drink and yank it back out and take return it. at least it will be much easier taking it out this time with nothing seized up...

 

get a full refund and buy one somewhere else... if they sell faulty products they dont deserve your business

 

Battery may show decent voltage, but it's the amps that count.

 

that's a good call. i have it out and i will take it back tomorrow and from now on i will ask that it be tested when i buy it.

my voltmeter only goes up to 10 amps. i tried to check the battery one time and almost welded the tip to the negative terminal i'm not really familiar with using it to check amperage...

 

lol. Car batteries have much much much more amps. What type of meter do you have? It's probably toast now?

 

yeah i know i was lucky i guess, i pulled it away quick with just a little spark but it was enough to slightly melt the tip. it's a normal multimeter, i don't remember where i got it. strangely, it didn't blow the fuse

 

There are tools available for specifically testing the alt...

 

well i took the alt. back to autozone today and they put it on the tester. after an embarrassingly long time, the guy got it hooked up right and tested it and it failed. so he got another one and i told him to test it because i was curious(even though i was getting my money back). it failed too! they quickly appologized and gave me my money back including the core charge since i already turned it in and i would not have it to give to the next place. so i got one from advanced and it tested ok plus i saved $30. guy at the counter told me he worked at az for three years and saw many new starters, altys, and batteries returned. moral, don't get that stuff from autozone...

 

I had a month old altenator go from autozone,You can easily get a bad one.

 

Sorry to bring this back from the dead.

I am having the same problem. First got my battery and brake lights coming on back in November. After about 2-3 weeks, it was getting to where lights were dimming and such. Replaced just before the new year. After about 2 weeks, I have the lights back on again. I just say "f" it, y'know. Take it on a road trip from FL to WV last month. By the end of the trip, the lights are dimming pretty bad. And now, about 2 weeks later, the lights and engine are 'pulsing'. At a warm idle, it pulses about twice a second. Stuck a voltmeter to it, got readings anywhere from 11.1 to 15.2. I picked up yet another alternator from AutoZone today. I am going to install it tomorrow morning and pray that it works. They made me pay the full price of $270, and then when I bring the other back, I'll get it all back.

Also hoping this doesnt destroy the computer because of the voltage variance. Any thoughts on this? My other question was:

I know the voltage regulator is inside the alt, but is there a chip in the ecu that controls the flow of juice?

Thanks bunches.

 

There is nothing in the ecu that controls how much amperage and voltage the alternator puts out. Its all done by the voltage regulator in the alternator. I hope that you have checked the drive belt is in good condition and has good tension. But it does sound like a bad alternator.

 

Yeah, I replaced the belt the last time when I put the new alternator in. I may have the belt a bit bit over-tight if anything, but everything seems to be in good working order. no shorts anywhere, the car, electrically, is basically back to stock. no grounding kit, no stereo, no amps, etc.

Weather permitting, I will get it changed in the morning. Hope it doesnt take 3 hours like last time.

 

I was told by a guy that rebuilt alternators for parts houses and he said he only replaced parts in it that were bad, so some of the parts never got replaced its no wonder some of these fail if what he said is true...this was while back with my IROC charging problem

 

on my 93 Altima the first Autozone alty was not giving power out. The second one had a bad bearing and was glowing red third one so far so good. It is very possible to have a new reman from autozone be bad.

 

autozones reader will only work if the battery is charged all the way so... i was told never to buy anything like that from there again but i replaced it with 2 different ones

 

Remanufactured Alts have lifetime warranty. Get them replaced when they do not work. Although you will have to do the work to change it out. Not bad really. After you do your 1st one, the 2nd would be a breeze!

 

UPDATE: Everything seems to be fine with the new one in for 24 hours and about 40 miles into it. Will repost if goes down the tubes again.

Only took me barely an hour and fifteen minutes.

 

We all love happy endings.

 

I agree