Let's see if any of you might know the answer to this: Generator light is always on, used to occasionally go out with a little driving but would always come on with the headlights on. Now it's just always on. Replaced Battery, Alternator, and rebuilt starter. All electrical connections are tight, static battery voltage is >12.2V, voltage across poles while running >14.4V. Still, the Gen light won't go off. Anything I'm missing here? Anyone have any ideas?
Appreciate any comments.
MK

I think you're looking at an internal problem w/ the alternator... the lights dont usually come on unless there is a voltage difference between the bat voltage and the expected output, which you confirm to be high enuf...

You MIGHT check for voltage drop between the alternator output and the battery... tho I don't really think that's where it is.

The good news is, that the regulators on those are REALLY EASY to replace, and should not be all-that expensive. A regulator swap-out could be the easiest way to confirm the problem...

Good luck! :)

Thanks Leeb,
Rather than swap voltage regulators, I had installed a brand new alternator- the second one actually- and still experienced the problem. If the battery sems to get enough juice from the alternator, is it possible that the fault could be with the generator light assy itself? Or maybe my testing is flawed, and in that case, what else should I be testing? And how?
Someone correct me if I'm wrong here but the circuit works something like this: Engine running, current is sent from bat+ to the starter assy, from there current flows to the chassis wiring and to the ignition coil. The battery can power the engine for a limited time, but the generator should push enough voltage into the bat+ terminal to both run the engine/accessories and charge the battery. The generator light is wired directly to the alternator and functions independently, measuring the current output of the voltage regulator in the following circuit: voltage regulator -> generator light -> capacitor -> chassis ground. Is there a way to measure current output at the alternator BAT terminal independant of the battery voltage? Can that be comared to voltage readings of the gen light circuit? Do I have any idea what I'm talking about?

IF I REMEMBER correctly...

The 'GEN' light is wired something like this...

One side goes directly to 12v, a battery source and
the other side is 'resistored' to ground, and has output from the alternator attached before the resistor.

While the voltage/current on both sides is 'even', meaning around battery voltage, there is no 'potential difference' between the two sides of the light and it stays 'off'...

When the output of the alternator falls below the voltage available from the battery, the balance is disrupted, and the higher-side voltage then flows thru the resistor to ground, and lights the bulb...

As I understand it, this resistance is built-in to the alternator's regulator circuitry and directly feeds the 'balance' side of the light.

THE ONLY OTHER THING I can think of is....
if the side of the light that SHOULD be providing 12v is being grounded, you would basically have a 'reverse connection' condition going on.

Something I mentioned earlier...
You could take a voltage reading at
1) the back of the alternator, and
2) the pos battery terminal.
--not to ground, but to each other--

There should be NO voltage displayed.... or DAMN LITTLE. If it's showing more than 1v the wire from the alternator to the battery has developed a resistance.... might do something, might not.

Something suddenly sprang into my head...
Do you have any other issues, like gauges that don't work? I seem to remember that, when my oil pressure/choke heater went south, it blew the gauge fuse and the GEN light would come on... and the gas gauge would not.

Replacing that fuse would blow as soon as the IGN was on unless the oil sender connection was taken off...
Might have something to do with it...

Or I could be snorting too much Diet Pepsi...
:)