Alternator/battery light

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kmkk1010
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Alternator/battery light

Postby kmkk1010 » Fri Aug 10, 2018 9:43 pm

Hey all ! Trying to figure out why my battery light is flickering. At a red light with headlights/brake lights and ac on, batt light turns off. Once accelerating, local and on highway, batt light flickers anywhere between dim and bright. Tested voltage under load at alternator (14.20 at idle/15.20 @2000 rpm) and at battery (13.00 at idle/13.93 @2000 rpm). Also tested negative side volt drop at 0.05 volt and positive side at 1.10 volt. I believe this is the original alternator on this 1995, 50,000 mile Beretta 3.1 base model. Do you think the internal voltage regulator is to blame or should I be cleaning up my connections at the engine ground and starter or both? By the way, battery is new - although this problem existed with old battery too. Thanks!



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Rettax3
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Re: Alternator/battery light

Postby Rettax3 » Sat Aug 11, 2018 3:47 am

Hi kmkk1010,
15 volts is a little on the high side. It could be your regulator, this is not a common problem, but it certainly could happen. Cleaing contacts is ALWAYS a good idea, if it isn't too much trouble for you -consider it preventive maintenance if nothing else. I would recommend also making sure the 'sense' wire is good (smaller red wire on most GM alternators of the era). If it is corroded, I have heard of people experiencing excessively high voltage as the regulator doesn't think it is putting out enough to power the car. Good luck, keep us posted.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

kmkk1010
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Re: Alternator/battery light

Postby kmkk1010 » Sat Aug 11, 2018 12:02 pm

Thanks Rettax3. Can you tell me where the sense wire runs to and from? The voltage reg. is internal on my alternator, right? I saw a voltage reg. sold separately, but I believe it was for certain 4 cyl models. Anyway, sometimes my voltage under load is as low as 12.50v at idle and up to 15.20v when revving, so voltage regulating is out of control. But I will be cleaning up any wire ends I can get to at my next oil change in a week or two. Is 1.10v drop on the positive side an indication of maybe a poor connection on the wire ends? Please let me know about the sense cable location. Thanks for help.



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Rettax3
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Re: Alternator/battery light

Postby Rettax3 » Sat Aug 11, 2018 5:25 pm

Not really sure where it terminates in the harness. Just check continuity at the alternator connector vs battery positive with the ignition switch on (and battery disconnected).

With that much voltage fluctuation and such a low voltage intermittently at idle, I would suspect the alternator (probably the regulator inside it -you can purchase them separately, but rarely do people bother to rebuild the alternators themselves anymore).

On my '89 RS Camaro (5.7 Police Special), I started to have an intermittent alternator failure. I replaced the alternator with a reman, but it did the same thing -voltage would occasionally start dropping out until it hit a low under 10 volts, then it would spring back up and charge at a healthy 14.2, +/-. I swapped the new alternator into another Camaro ('88 IROC-Z), and it did the exact same thing. I warrantied it out, guess what? SAME THING AGAIN, but only when it gets warm. So, even if you replace the alternator and the symptoms persist, it could be a defective replacement. Those POSs I got were from O'Reilly, BTW.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

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Re: Alternator/battery light

Postby GT_Indy » Sat Aug 11, 2018 5:44 pm

Rettax3 wrote:Not really sure where it terminates in the harness. Just check continuity at the alternator connector vs battery positive with the ignition switch on (and battery disconnected).

With that much voltage fluctuation and such a low voltage intermittently at idle, I would suspect the alternator (probably the regulator inside it -you can purchase them separately, but rarely do people bother to rebuild the alternators themselves anymore).

On my '89 RS Camaro (5.7 Police Special), I started to have an intermittent alternator failure. I replaced the alternator with a reman, but it did the same thing -voltage would occasionally start dropping out until it hit a low under 10 volts, then it would spring back up and charge at a healthy 14.2, +/-. I swapped the new alternator into another Camaro ('88 IROC-Z), and it did the exact same thing. I warrantied it out, guess what? SAME THING AGAIN, but only when it gets warm. So, even if you replace the alternator and the symptoms persist, it could be a defective replacement. Those POSs I got were from O'Reilly, BTW.


I've been there before. I bought an autozone alternator and 7 alternators in a row failed, then I stopped and bought a Single wire Powermaster from Summit Racing for my car. And its higher Amp output (but the smaller pulley also takes a bit smaller belt). They have stock style ones too. Never had trouble again.
That cheap alternator I got from autozone is a Lifetime replacement as long as I show a receipt, but I got tired of replacing it once a day after going only 5 miles. (Yes I did that for 7 days in a row). The 8th alternator I never used, its been a paper weight on my desk ever since. lol.
So I second getting a quality alternator from a reputable brand name.

Sometimes regulators go bad and become intermittent, if all connections test positive, its probably the alternator.
Places like autozone can test your alternator, but that means removing it from your car, and it may not always test bad if it only goes bad when hot/cold or under certain conditions.


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kmkk1010
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Re: Alternator/battery light

Postby kmkk1010 » Sat Aug 11, 2018 10:27 pm

Thanks guys for your help and suggestions. I'll post back with any results I get. Just wondering if anyone was able to remove and clean the engine grounding bolt and cable (which runs from the negative battery terminal) and how so. Thanks again !!



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Rettax3
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Re: Alternator/battery light

Postby Rettax3 » Sun Aug 12, 2018 1:51 am

kmkk1010 wrote:Thanks guys for your help and suggestions. I'll post back with any results I get. Just wondering if anyone was able to remove and clean the engine grounding bolt and cable (which runs from the negative battery terminal) and how so. Thanks again !!

The grounding bolt is a s straight-forward as any hardware, if you want it deep-cleaned use a small brush and either brake-parts cleaner or something like "QD" electric contact cleaner. I have personally never had or seen an electrical problem from oil or grease on the ground bolts, but it certainly could happen. I have seen cars so crudded-up with grease that the starter had issues not grounding properly, so same concept... Oh, and most auto-parts stores can also test starting/charging systems on the car now too, so you can probably test it all without removing anything. :good:


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

kmkk1010
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Re: Alternator/battery light

Postby kmkk1010 » Sun Aug 12, 2018 2:46 pm

Thanks Rettax3. Would you believe the Autozone guy told me that they couldn't test my battery, alternator etc. because the battery has side post terminals and that their test clamps can't properly grip the small bolts on side terminals. I said "WHATTT"!!!
Anyway, what I meant on previous post was how to best access the negative engine ground bolt. It is all crudded up with green corrosion and it's in a pretty tight space. Thanks again for all your quick responses and help.



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Re: Alternator/battery light

Postby GT_Indy » Sun Aug 12, 2018 3:05 pm

kmkk1010 wrote:Thanks Rettax3. Would you believe the Autozone guy told me that they couldn't test my battery, alternator etc. because the battery has side post terminals and that their test clamps can't properly grip the small bolts on side terminals. I said "WHATTT"!!!


What...
They are supposed to have these on hand:
(If not, Walmart sells them, and the auto store should also have them on the shelf)
https://www.walmart.com/ip/Everstart-92 ... s/16006672
Either way, it shouldn't matter, if it can clamp on, its good enough.

kmkk1010 wrote:Anyway, what I meant on previous post was how to best access the negative engine ground bolt. It is all crudded up with green corrosion and it's in a pretty tight space. Thanks again for all your quick responses and help.


Are you talking about the ground bolt on the bell housing next to the radiator? Or the other one on the bell housing by the firewall?


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kmkk1010
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Re: Alternator/battery light

Postby kmkk1010 » Sun Aug 12, 2018 4:18 pm

The one closest to radiator facing forward on driver side...



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Rettax3
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Re: Alternator/battery light

Postby Rettax3 » Mon Aug 13, 2018 4:41 pm

Make sure when you loosen the nut holding the wires to the stud-end of the bolt that the entire bolt doesn't turn with it -you will twist-off the ground connectors if you keep spinning the bolt. You might need an 18mm open-end wrench to hold the bolt-head while using a 15mm to remove the nut holding the wires on. I've found an extension with a wobble-end is the easiest way to access those bolts with a socket.

Customer-service isn't what it used to be. I am usually pretty nice and patient with people, but if they are that lazy/stupid/ignorant, I am reaching a point of intolerance for it. Ask for someone who knows what they are talking about, or who at least gives a $#!t.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

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Re: Alternator/battery light

Postby GT_Indy » Mon Aug 13, 2018 5:06 pm

Rettax3 wrote:Customer-service isn't what it used to be. I am usually pretty nice and patient with people, but if they are that lazy/stupid/ignorant, I am reaching a point of intolerance for it. Ask for someone who knows what they are talking about, or who at least gives a $#!t.


Yup. Sometimes its better to leave and find a competitors store. Not all auto stores will say the same thing, usually. Sometimes they price match each other as well.


96 Beretta Z26 swap
90 Beretta GTZ
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kmkk1010
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Re: Alternator/battery light

Postby kmkk1010 » Mon Aug 13, 2018 6:19 pm

Ok, thanks....I will give it a try. Yeah I remember 15-20 years ago, you could walk up to the parts counter and you'd find a guy dying to help you and he would already know your problem before you even finished explaining it.. someone who had been in the trenches. Now, they hire anyone who can point a mouse and pull the referenced part and guess the rest..



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Re: Alternator/battery light

Postby Rettax3 » Tue Aug 14, 2018 2:38 am

kmkk1010 wrote:Ok, thanks....I will give it a try. Yeah I remember 15-20 years ago, you could walk up to the parts counter and you'd find a guy dying to help you and he would already know your problem before you even finished explaining it.. someone who had been in the trenches. Now, they hire anyone who can point a mouse and pull the referenced part and guess the rest..

15-20 years ago, there was no such thing as GDI. 15-20 years ago, there were 15-20 years less of car models and associated parts. Now you have cars where the power window switch is a 'computer module' that will communicate with other on-board computers, but won't talk to you or the $200 scanner you just bought at the parts store. Now you have cars that don't run right if you replace the headlight bulb with something different (long story behind that one, but stupidly true). The game is different, some say evolved, I say maybe but maybe devolved in some aspects too. Legitimate repair shops have a hard time keeping up with all the changes across all of the manufacturers. A parts-supply store has no chance, especially since they are competing with online parts-suppliers, they don't pay much better than minimum-wage so who with half a brain would stay there long enough to get good at it unless they just liked the work? Those are few and far between -be thankful if you can still find someone behind the counter who even knows what plastigage is. But expecting the 10-buck-an-hour shmoe to do his/her job and use the test-equipment the store gave them to keep you as a customer is not too much to expect. I would be asking to use their phone to dial the numbers on their front door. :no:


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

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Re: Alternator/battery light

Postby GT_Indy » Tue Aug 14, 2018 8:51 am

Rettax3 wrote:
kmkk1010 wrote:Ok, thanks....I will give it a try. Yeah I remember 15-20 years ago, you could walk up to the parts counter and you'd find a guy dying to help you and he would already know your problem before you even finished explaining it.. someone who had been in the trenches. Now, they hire anyone who can point a mouse and pull the referenced part and guess the rest..

15-20 years ago, there was no such thing as GDI. 15-20 years ago, there were 15-20 years less of car models and associated parts. Now you have cars where the power window switch is a 'computer module' that will communicate with other on-board computers, but won't talk to you or the $200 scanner you just bought at the parts store. Now you have cars that don't run right if you replace the headlight bulb with something different (long story behind that one, but stupidly true). The game is different, some say evolved, I say maybe but maybe devolved in some aspects too. Legitimate repair shops have a hard time keeping up with all the changes across all of the manufacturers. A parts-supply store has no chance, especially since they are competing with online parts-suppliers, they don't pay much better than minimum-wage so who with half a brain would stay there long enough to get good at it unless they just liked the work? Those are few and far between -be thankful if you can still find someone behind the counter who even knows what plastigage is. But expecting the 10-buck-an-hour shmoe to do his/her job and use the test-equipment the store gave them to keep you as a customer is not too much to expect. I would be asking to use their phone to dial the numbers on their front door. :no:


Yah everything is becoming more computerized on cars. I believe 1982 they had computer controlled carbs and people used to think those were complex. I think another 40 years and todays cars will be childs play compared to future cars.


96 Beretta Z26 swap
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