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I have a 94 MX6, 2.5LV6, 5spd with 163,210 miles. My alternator went out this weekend. I know this because I have a voltage meter installed and it was reading 11.2 VDC. When I would rev the engine, it did not change at all.
Took it to Advanced Autoparts and they tested the system and determined there is zero voltage coming from the alternator. This explains also why, after a 250 mile drive, when I put my battery charger on it was pulling 10 Amps. I must have been running on pure battery power the whole time.

Anyway, I noticed that the Charge warning light did not light up. Its the one that looks like a little battery. It is suppose to light up when you first switch the key to accessory and stay on until you start the engine. When the alternator starts producing voltage is goes out. I don't know how long its been that the light doesn't come on when switching the key. Never noticed it missing.

Anyway, I pull the instrument cluster to check the bulb. It was ok. I checked the voltage on that socket and I get Battery voltage 11.5 VDC.
The weird thing is it will not light the bulb. Put the bulb in any other socket and it lights up just fine. But in the Charge socket it won't light up (EVEN THOUGH I KNOW THERE IS BATTERY VOLTAGE THERE). I lightly sanded the connections to get rid of corrosion. Didn't help. I bent the two prong on the male piece that hold the bulb so that it would make good contact. Still won't light.

I have a spare instrument cluster. So, I plugged it in and it does exactly the same thing. So, for some reason the charge circuit provides the necessary voltage to light the bulb, but not enough current -- I guess. I connected an LED to the terminals of the charge socket and it light up, but dimly.

Any ideas what is happening?

Any help would be greatly appreciated.
 

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You will find that the regulator on the alternator has failed, the warning bulb goes back to the regulator.
 

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Discussion Starter #5
No Charge Warning Light Reply to Thread

Could the bulb be burned out?
With respects, read my original post. I pulled the instrument cluster and check every single bulb including the charge bulb. THEY ARE ALL GOOD! Replaced the alternator on Sunday and my charge light is back as normal. I think the post talking about the regulator being bad is correct. I just don't know what kind of a warning light does NOT go on when the alternator fails cause the regulator fails. Regulator must of failed in such a way as to represent a open circuit. Only thing I can think of.
 

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Hi guys I have the Mazda Mx6 1993 model my battery light was just starting to get brighter as I accelerate but was still charging but then just stop charging I bought a new alternator still not charging when I remove the battery cable the car dies any help please
 

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The same thing happened to me once. The new (i.e. remanufactured) alternator was bad. It seems this happens a lot.

But first double-check all the connections are clean and tight.
 

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Is the best way to check for this to put a meter on the battery when the car is not running (to check battery voltage), and when the car is running (to see if alternator is putting out voltage) ?
 

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Goodbar: yes, I think so. Because running the engine with battery disconnected can result in voltage spikes, which can damage the electrics (or so I've read).

Should be around 14 volts with engine running, and 12.5 volts otherwise.
 
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