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Generator light issue

1996 Mazda Protégé, 129,000 miles

A week ago, generator light went on very dimly when starting and driving a very short distance, then it went dark to normal. Just wondering what would cause this problem, if it is even a problem.

Replaced in 2010.

Thankyou in advance!


Easiest thing to check would be the drive belts are loose, next would be loose connections - i doubt it would fail after such a short time but it is possible.

I’d have the belts checked, have the tension checked (the belt tensioner might be getting weak allowing slippage), check the battery cable connections for any evidence of looseness or corrosion, and have the battery and alternator/generator/rose-by-another-name tested.

Is it a problem? It’s more of a “heads-up” that a problem is developing that will probably cause you to end up on the side of the road with a dead battery. I would definitely follow up on this.

“i doubt it would fail after such a short time but it is possible.”

It certainly is possible

On our fleet vehicles, we sometimes install NAPA remanned alternators, when the vehicle needs to be done yesterday

Unfortunately, they don’t seem to last much longer than 2-3 years

Get one of these and put it in your 12V receptacle:

It should read about 14V while the engine is running. If it does not turn off with the key out, then remove it when the engine is off.

Thanks, insightful. I’ve never seen one of these. I like it. I guess maybe I should get out more.

The alternator/generator does sort of look like a mechanical rose in some ways. Love the analogy. I too will order one of the INNOVA 3721 Battery and Charging System Monitors.

Thanks for all of the suggestions!