Alternator Light

[bytes311]

While browsing the forum for answers to another question, I came across a thread discussing the alternator light in the dash, and how the alternator will not charge the battery if the light doesn't work. This prompted me to check my own alternator light. Sure enough, the light did not illuminate in the key ON position or after engine start.

I've owned my car for three years now, runs great and everything, but the alternator light never crossed my mind until recently when I FINALLY got my AC work done, and running the AC would overload and kill my engine (or kill the ECU which in turn kill my engine). This lead me to believe that the alternator isn't putting out enough juice.

I removed the dash binnacle and inspected the circuit board and found that somebody once tried to use pliers to remove the alternator light bulb and broke the contact between the bulb and the circuit board. I repaired the board and swapped bulbs with the door ajar and now the light works, HOWEVER, it only illuminates with the engine running, and NOT in the key ON position. And when I rev the engine, the light illuminates brighter.

Does this sound indicative to a bad alternator? And wouldn't my battery be completely drained at this point?

Thanks

[PJ Grady Inc.]

Your car originally was equipped with a Ducellier alternator. Is that what you still have. If so replace it as it is a terrible alternator. If your dash repair was successful then the alternator is probably bad as the light would indicate.
Rob

[DMC-Ron]

I'm going to check my alternator indication. It occurred to me that the alternator indicator could potentially give warning of a belt failure that, in turn, provides a early warning of a coolant failure. I'm new, so I guess everyone already knows this, but it seems prudent to check and see if the alternator fail is working.

Ron

[David T]

Many stores like Auto Zone will test your alternator and battery for free.

[rtcraver]

If your alt is not putting out enough juice (as the original won't) go ahead and upgrade to a 100 or above amp... Not that expensive and worth not having other issues (like a/c stalling the engine) occur to give you headaches... ;-)

[bytes311]

Thanks guys. Yeah, my car does have the original Ducellier. I'll go ahead and get that replaced. Is there a market for the Ducellier, or should I just dispose/recycle it?

[DMC5180]

I'm going to check my alternator indication. It occurred to me that the alternator indicator could potentially give warning of a belt failure that, in turn, provides a early warning of a coolant failure. I'm new, so I guess everyone already knows this, but it seems prudent to check and see if the alternator fail is working.

Ron

Yes, a sudden BATT LIGHT illumination while driving usually means you've lost the alt/water pump belt and you should pullover immediately to verify.

If the the BATT LIGHT starts to flicker on/off and you see volt fluctuations on the gauge, this is typically a sign that you alternator brushes are worn out but the belt is still in place. ( I've had this experience on a Daily Driver) lots of warning that the alternator was dying before it actually did).

There are exceptions, but I am speaking in terms of an otherwise Healthy Charging system. (Good grounding and good wiring connections)