What is the core function of the battery light on cluster
 

If anyone has been following my string of 12V issues.....

Anyhow, question of the day. What is the function of the battery light on the cluster

Got around to popping a new alternator in. I'm hoping this is the fix........
Never Ever got a battery light on the cluster

To sum it up.
Burned up 2 batteries
Root cause I suspect that both times, I was literally driving the car and running off the battery until it either shorted out/drained way too far/too fast. And or Alternator acts up during when the car got hot - really hot ?
Most of the daily drivers is anywhere from 16-20 miles and then back.
Both instances, when the battery died, it was a 60-70 mile trip.

When looking at alternator with MM and amp clamp, it's always been putting out power at correct V.

I've had multiple drives in between the last 2 months, but I was putting the battery on a charger whenever I saw the voltage after rest dip under 12.6. I suspect this compounded/masked my battery/capacity issues during the days/weeks I was messing with this...

every time i had a red battery light come on it turned out to be a bad alternator.

Battery light says nothing about the battery, it warns you that the battery is experiencing a discharge. While that could be due to the battery, it could also be due to the alternator, regulator, or wiring.

Indeed. I've had the battery at a high discharge (ac, audio) assuming all is well with the car only to come back and be in a no crank situation, etc, etc - toasted battery. We're talking brand new batteries. Neither instances ever exhibited any warnings on the cluster.....

Both times to the point, car just shut off. Luckily both times, I was on local street

Just for shchitz and giggles and I have one more thing I think I have not looked at....

If any of ya'll have a amp clamp, by just starting the car, how many amps is the alt pushing out and declining...When I measure it, it was approx 45 declining downward

Re-Re-Checked earth to block. All is good.

Based on all the symptoms, it has always pointed to the alt.

Just kinda strange, I never got a bat. light lit up on the cluster.
I would think either low volt, no volt, low current, something would have surely triggered it or at least flicker it

All I can is ahhhhh......new alt did the trick.

What compounded the diag was the fact that in between testing/isolating, I was putting the X on a charger...

X would be okay on local small trips as I pretty much charged her back up,.
Not so much when I took a long one......

Bottom line.
Never a error on the cluster
I suspect it was getting proper V , alternator just not putting out enough A. Long drive, vehicle drawing off the battery, etc, etc.

I thank the big guy up there, as both times it straight up shutdown on me when I was driving, I was on a local street.

glad to here you got it all sorted out,

Glad it worked out for ya. It's a good feeling

The battery light is not a battery light at all, it's a Charging System Light. The light means, ALWAYS, that there is an issue with the charging system, and the issue will be the alternator nearly 100% of the time. The times it isn't the alternator, then it is in the connection of the alternator to the rest of the car. There is no light to tell you that the battery itself is unhappy with its life, or the job that is is assigned to carry out.

JD -

In my case, my alt was putting out correct V. It was not putting out enough current.
The light never ever flickered or lit up

If the voltage is right, 14.5 when the engine is running, but the power is low, then the voltage must fall to a level that is below the specification.

If the engine is running and there is no load, then the voltage will be, or should be, 14.4vDC or there about. If the system has a heavy draw, AC is on, radio, lights, and other electrical loads, but the current is weak, then by definition the voltage must fall. It is a requirement of Ohms Law that when the power -- voltage -- is fixed but the current is low, the voltage has to be low. It has to be.

When you are facing this sort of problem, turn on all of the electrical loads you can find, then see what the voltage supplied by the alternator is. If the current is below specification, then the voltage has to suffer under heavy loads.

If you are driving around in daytime, and the battery survives the ordeal, but leaves you stranded at night, then you have low current provided by the alternator. This condition might not be indicated by the Charging System Light. You should have low voltage at this time as well. If current is low but the load is high, the voltage will drop while the system struggles to provide the power that is demanded.

Woot Woot.
2 Days of Driving and I'm pretty positive the hiccups are done.
I can now unload my car and make the X back the soccer toddlers car back again.

Ahh....I've got my 2 years worth of wrenching. Hopefully no more until Summer 2016
\\\Did I just jinx it