Battery Light

I have a 91 SC1 with about 114,000 miles on it. The car has been pretty
decent over the past few years as long as I keep an eye on the oil level


Recently the battery light started to come on while driving the Saturn. It
does not always stay on and there really is no predictable pattern as to
when it comes on. The battery was replaced about 5 years ago and it seems
to be fine (no struggle when starting car at low temperature below 30
degrees). The altenator was also replaced about 3 years ago.

This has been happening for a couple of weeks and the car seems just fine.
Any ideas as to what is going on?

I also tried to see if I could get the light to go on by running the
lights, heater fan on full, radio, rear defogger, etc. but the light stayed
off.

Thanks,
Dan

 

5 years? My money would be on the battery. I think you are living on
borrowed time. Most places that sell batteries will do a free electrical
system charging check to make sure the alternator and voltage regulator are
OK.

Bob

 

Could be the battery getting weak or the altenator/regulator going bad..
most garages will test this for you.. They will perform a load test on teh
battery and the charge pull of the altenator. they will also test teh amps
coming out of the altenator to see if it's up to spec..

 

5 years is a good time for a new battery, either that, or the belt is
slipping.

 

5 years? My money would be on the battery. I think you are living on

The only problem with what you guys are saying is that even if the battery is
dead, the light won't come on unless the alternator isn't charging.

 

On most vehicles if the battery has a shorted cell it will reduce the
voltage and trigger the battery idiot light. Again, my money is on the
battery, but I agree it could also be a slipping alternator belt, although I
would expect you would see this most often under load and lower RPMs which
did not match the description. The battery most likely has sulfur deposits
and is internally shorted from age/use.

Bob

 

Thats why I suggested to go to the auto store or garage and have the battery
load tested and altenator charge pull and amperage draw.

 

I've never known a battery ligth to come on due to a bad battery,
unless it was totally gone. Sounds like an alternator problem.
Probably an intermittent contact in the alternator. You can
probably safely drive the car until the problem becomes more
persistent (though keep a set of jumper cables in the trunk).

 

On most vehicles if the battery has a shorted cell it will reduce the

If a cell is shorted it may cause enough potential difference with the
alternator to trigger the light.........but, a shorted cell should be
consistent.....

 

I've never known a battery ligth to come on due to a bad battery,

Thats what I'm saying........

But, if the alt decides to totally go, jumper cables won't help........sure you
can get it running when the other battery is hooked up, but you won't go far
after the cables are unhooked.......

 

(BANDIT2941) wrote in

Thanks for all of the feedback.

Just to shed some light on the subject, it is very unlikely that a slipping
belt is the problem. I replaced the belt tensioner about a year ago and
the belt is in good shape. Not to mention, I have not heard a belt squeek
from under the hood.

After driving the car some more today, it seems like the light is not on
when the car is first started but may come on after 10 minutes or so.

I am going to get a new battery since the current one is 5 years old. It
will die sooner or later anyway.

Dan

 

I'm guessing it's the alternator, with an intermittent failure.

Others will say "but the alternator is only 3 years old"... but these
Delco alternators really aren't all that great to begin with. Did
you get a brand-new alternator or a rebuild? Some rebuilt units are
better than new, others are not so reliable.

Tim.

 

I'm guessing it's the alternator, with an intermittent failure.

That pretty much sums up my thoughts........

 

It's the alternator!! The only reason the warning light is shaped like a
battery is so it could be understood by someone of any language. Until the
70s it usually read [ALT].

You can ruin a new battery (or an old one) by running it discharged flat,
like you'd do if your alternator dies next week and you need to drive home.
You can even ruin a new alternator by charging a flat battery before its
brushes seat well.

Moral: Get checked out, don't be suprised if you buy both.

 

You can charge the battery off another car and have enough juice to
get home or to the dealer.

 

You can charge the battery off another car and have enough juice to

As long as you're not going far, its during the day, and you have time to sit
hooked up to the other car for a bit.........