Battery Alternator Issues Need Help!

Joined
Jul 17, 2014
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6
1997 c5 ls1. Ok so about a week ago my car got a "charge system failure" message. I did some research and decided it probably wasn't a big deal so I kept driving..
Couple days later I'm driving down the road, and my front speakers go out.. So I'm thinking it must be a ground wire behind my radio. So I'm in the middle of nowhere so I keep going. About a mile later, all my lights start flashing, and everything on my instrument cluster(all the gauges) start going from 0/200, bouncing back and forth. It was Crazy. So I was about to pull over and then engine shuts off. I was luckily able to coast into a parking spot at a dollar general. I then sat for a minute, tried cranking my car and got the dead battery clicking. The whole time I was thinking it was my alternator. But somehow I had some corvette guys convince me I had a bad battery, so I went and bought a new battery. Car drove great all the way home until I got another charger system failure. Next day I took it on 2 60mile trips and it drive fine but I noticed when I was driving at night my lights weren't very bright, and my voltage was only at 10.5> volts.
Since then I've taken my alternator off, taken it to an alternator shop. Had the guy take it apart and check it out and showed me that it is working. (He had some machine show me).
I don't know what to do next...
Need help...
 
Maybe the battery dropped a cell or two... or has sulfated to the point that the internal resistance is too high... Lead-Acid batteries don't like heat and only last reliably for 4-6 years depending on how they are treated...

see if the battery will take a charge with an external charger

If it does then charge it... then take a volt meter and check the voltage across the terminals if it aint in the range 11.5 or 12 volts then you have some issues...

under 11 volts its dead Jim...

take the battery to an auto parts store and have them load test it if you want...

also when the car is running the voltage across the battery should be on the order 13-14 volts... though some of the newer charging systems vary the output of the alternator to save fuel... less than that and the alternator is not likely working properly... as always YMMV

hope this helps
 
Sounds to me like the diodes are shot and you are throwing out a lot of AC voltage from the alternator. Your lights will handle DC as well as AC....Electronics not so well.

Years back I had a similar issue- battery was putting out some serious gasses trying to handle the AC not filtered from the Alt. Your new battery filtered the AC for a while-did you notice any rotten egg smell from the battery.

Put your meter on AC and see what you've got- at the alternator- seeing more than .5volts AC that's you problem.

Let us know how it turns out-

Richard
 
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Sounds to me like the diodes are shot and you are throwing out a lot of AC voltage from the alternator. Your lights will handle DC as well as AC....Electronics not so well.

Years back I had a similar issue- battery was putting out some serious gasses trying to handle the AC not filtered from the Alt. Your new battery filtered the AC for a while-did you notice any rotten egg smell from the battery.

Put your meter on AC and see what you've got- at the alternator- seeing more than .5volts AC that's you problem.

Let us know how it turns out-

Richard

6 diodes in a pack, 3 phase winding output, so a full wave bridge.....if you have a shorted diode pack you have a flame out.....if you have a open diode all you have is reduced output.....mostly noted at idle.....depending on the loads at whatever speeds involved....

I suspect something in the regulator feed wires, the alt dunno what is going on in the car because of some connection/wire/fault.....do you have a red idiot light?? does it glow at night, but not bright enough at daylight??

I still suspect the alt is bad, regardless of bench test....just a SWAG....


:surrender:
 
Yea idiot light was on earlier.. Im thinking it's alternator as well. Somebody mentioned something about the starter though too on another website..
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Yes I know my oil gauge and battery gauge doesn't work.
And here's something else that happened:
When I turned on my headlights, my dash lights stopped working completely
 
Yes I know my oil gauge and battery gauge doesn't work.
And here's something else that happened:
When I turned on my headlights, my dash lights stopped working completely

THAT smells like a bad ground to me......I can only make general comments as I have never played with a newer vette than my old '87, which was years ago.....

:surrender:
 
Yes I know my oil gauge and battery gauge doesn't work.
And here's something else that happened:
When I turned on my headlights, my dash lights stopped working completely

THAT smells like a bad ground to me......I can only make general comments as I have never played with a newer vette than my old '87, which was years ago.....

:surrender:

Would it be ok if I ran 8 gauge wire from negative side of battery and connected it to the grounds?
 
Yes I know my oil gauge and battery gauge doesn't work.
And here's something else that happened:
When I turned on my headlights, my dash lights stopped working completely

THAT smells like a bad ground to me......I can only make general comments as I have never played with a newer vette than my old '87, which was years ago.....

:surrender:

Would it be ok if I ran 8 gauge wire from negative side of battery and connected it to the grounds?

I"m a old ET here, so for me to rip through the car with a volt meter is about second nature to me, I maybe even have to have a wiring diagram, especially on something newer, like what you have....I would be taking voltage readings on various parts, like from battery negative to frame, then from frame to engine, then birdcage, and then instrument panel grounds/frame.....this all with engine running....

On the alternator, there is a plug on the side, has several wires in it....but some cars have just ONE wire in that plug, it's brown in most cars....and goes to terminal L stands for light, as in idiot light, it should have full voltage on it...like if your alt is putting out say 14 volts, you should have nearly 14 volts on that L terminal.....if there is very little voltage differential between the output stud of the alt, and point L on that regulator plug, I have to condemn the alt.....:surrender:
 
Yes I know my oil gauge and battery gauge doesn't work.
And here's something else that happened:
When I turned on my headlights, my dash lights stopped working completely

THAT smells like a bad ground to me......I can only make general comments as I have never played with a newer vette than my old '87, which was years ago.....

:surrender:

Would it be ok if I ran 8 gauge wire from negative side of battery and connected it to the grounds?

I"m a old ET here, so for me to rip through the car with a volt meter is about second nature to me, I maybe even have to have a wiring diagram, especially on something newer, like what you have....I would be taking voltage readings on various parts, like from battery negative to frame, then from frame to engine, then birdcage, and then instrument panel grounds/frame.....this all with engine running....

On the alternator, there is a plug on the side, has several wires in it....but some cars have just ONE wire in that plug, it's brown in most cars....and goes to terminal L stands for light, as in idiot light, it should have full voltage on it...like if your alt is putting out say 14 volts, you should have nearly 14 volts on that L terminal.....if there is very little voltage differential between the output stud of the alt, and point L on that regulator plug, I have to condemn the alt.....:surrender:

Sorry I'm new to this ground stuff... How do I check the ground with a volt meter? And alternator?
 
At the battery, you put the negative lead of the VM, you can use a clip lead to extend the negative VM lead, as you are going to check various chassis/engine/body ground spots....if you see any voltage to those ground points, you have proven you have some grounding issues, the metal parts are not allowed to 'float' everybody is connected to battery negative, one way or another.....I maybe allow 100 mv....that's .1 volt but anything much above that is bad....you really should get to your instrument ground but I dunno how you gain access on that.....

you know, another point, find you fuse panel, and check for identical voltages on each side of ALL fuses, with engine running of course.....or at least key on in the run position....:eek:
 
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