Charge Voltage ??
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Burning Brakes
Joined: Nov 2005
Posts: 908
Likes: 1
From: Colorado Springs Colorado
Charge Voltage ??
Was driving into town when I noticed the voltmeter (both analog & digital) were low, at one point it dropped to 11.2. I was turning around to head home when it started to rise all the way up to 14.5. This was a 6 month old NAPA alternator, so I took it back and upgraded to the 140 amp one with the lifetime warrenty. This one is running between 13.7 and 14.5 Volts. WTF? aren't they supposed to hold right at 13.8 volts? Did I get another lemon, or does the voltage wander a bit above 13.8 normally?
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Team Owner
Joined: Mar 2001
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From: Cincinnati, Oh USA
GM says anywhere from 13 to 16 volts is ok. Cold, C4 alternators put out 14.7 volts and because of the 0.3 volts drop across the ignition switch contacts, your dash voltmeter will read 14.3 volts. As the alternator warms up, its voltage drops to 13.3 volts so that continued driving does not, "outgas" the battery which occurs when the charging voltage is 14.2 volts or higher on a near or fully charged battery.
Drifting
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