Alternator output voltage
Thread Starter
Instructor
Joined: Nov 2017
Posts: 221
Likes: 172
From: Derby Kansas
Alternator output voltage
Anyone know what the output voltage should be? Last night I noticed that my batt voltage readout was only 12.3 to 12.9 volts. This seems low, but maybe its in the right range. Battery is new. I did have headlights on and AC was off.
2001 Base Convertible
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Melting Slicks
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This stickied post in the tech area says, "...check if the alternator is charging the system...voltmeter red lead on the alternator B+ stud and black lead to ground...raise the idle to 2000 RPM or so and turn on the AC, headlights, blower motor...the voltage should be around 13.5 -14.5 or so..."
https://www.corvetteforum.com/forums...post1604291849
The readout on your dash will be somewhat lower since it's not directly at the alternator but it should be within a half a volt or so under the same conditions (A/C, headlights, etc.)
https://www.corvetteforum.com/forums...post1604291849
The readout on your dash will be somewhat lower since it's not directly at the alternator but it should be within a half a volt or so under the same conditions (A/C, headlights, etc.)
Thread Starter
Instructor
Joined: Nov 2017
Posts: 221
Likes: 172
From: Derby Kansas
This stickied post in the tech area says, "...check if the alternator is charging the system...voltmeter red lead on the alternator B+ stud and black lead to ground...raise the idle to 2000 RPM or so and turn on the AC, headlights, blower motor...the voltage should be around 13.5 -14.5 or so..."
https://www.corvetteforum.com/forums...post1604291849
The readout on your dash will be somewhat lower since it's not directly at the alternator but it should be within a half a volt or so under the same conditions (A/C, headlights, etc.)
https://www.corvetteforum.com/forums...post1604291849
The readout on your dash will be somewhat lower since it's not directly at the alternator but it should be within a half a volt or so under the same conditions (A/C, headlights, etc.)
Drifting
Joined: Sep 2009
Posts: 1,862
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From: Prescott, Arizona
You must read battery voltage directly across the battery terminals with a volt or multimeter to see whether the alternator is charging. The DIC voltage can vary significantly if the battery terminals are not clean and tight or all engine to frame and other grounds in the circuit are not clean and tight.
If you do not have a multimeter, here is an inexpensive one that works fine for me-
If you do not have a multimeter, here is an inexpensive one that works fine for me-
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Melting Slicks
Joined: Sep 2008
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From: Espanola New Mexico
Always measure battery voltage at the battery terminals and also to ground and alternator output terminal. Many people forget that the alternator output is connected to the battery at the starter solenoid, and that connection point has been known to come loose and or corroded.
