Low Voltage Warning Light

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Doug308
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Location: St. Louis, MO

Low Voltage Warning Light

Post by Doug308 » Sun Aug 05, 2018 7:49 pm

Hi guys. Got ny first warning light since buying my 710 M a couple of months ago.

While driving on road (had been driving about an hour) my low voltage light came on. She kept running fine. Headlights were not on. However, turn signals worked and the fan worked as well.

The odd thing is that I had charged my batteries a few days before.Using directions I got from another post on this forum which gave directions on charging both batteries at once. As a simple fix, I was thinking that I should start by disconnecting the batteries and charging them separately. I understand that it could be a few things, but wanted to hear from the voices of experience what the most likely issues might be.
"When I was 13 I thought my father was the dumbest man alive. By the time I was 21 I was amazed at how much he had learned."

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Doug308
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Location: St. Louis, MO

Re: Low Voltage Warning Light

Post by Doug308 » Mon Aug 06, 2018 11:10 am

UPDATE; Okay, so I had both batteries tested and found that one of them was pretty iffy. Replaced that battery but am still getting the low voltage light. Starts and runs fine. But a light's a light.

Any suggestions?
"When I was 13 I thought my father was the dumbest man alive. By the time I was 21 I was amazed at how much he had learned."

Mark Twain

Doug308
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Joined: Mon Jun 18, 2018 10:28 pm
Location: St. Louis, MO

Re: Low Voltage Warning Light

Post by Doug308 » Mon Aug 06, 2018 11:10 am

UPDATE; Okay, so I had both batteries tested and found that one of them was pretty iffy. Replaced that battery but am still getting the low voltage light. Starts and runs fine. But a light's a light.

Any suggestions?
"When I was 13 I thought my father was the dumbest man alive. By the time I was 21 I was amazed at how much he had learned."

Mark Twain

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pcolette
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Re: Low Voltage Warning Light

Post by pcolette » Mon Aug 06, 2018 2:03 pm

My experience is that the warning light is an indicator of the alternator charging status. So, possibile causes are: - loose or worn fan/alternator belt, - failing regulator, - worn brushes in the alternator. Maybe a couple of other things too but those 3 are the most common. I'd start with the fan belt since that's the easiest. The belt, alternator and brushes are all available from the usual 2 sources. Good luck!
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undysworld
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Re: Low Voltage Warning Light

Post by undysworld » Mon Aug 06, 2018 3:30 pm

Don't forget to check the Molex plug too. Bad connections and/or corrosion there are an easy fix.
Check the sticky here for battery charging info, if you haven't.
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Doug308
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Location: St. Louis, MO

Re: Low Voltage Warning Light

Post by Doug308 » Mon Aug 06, 2018 5:40 pm

Thanks for the help guys
"When I was 13 I thought my father was the dumbest man alive. By the time I was 21 I was amazed at how much he had learned."

Mark Twain

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montieth
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Re: Low Voltage Warning Light

Post by montieth » Mon Aug 13, 2018 11:34 pm

Have you put a DMM on the batteries while running to see if the system is even charging?
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