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Charging system test

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Old 01-14-2008, 01:36 PM   #1
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Default Charging system test

Does anyone here know how to test the charghing system using a voltmeter?
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Old 01-14-2008, 02:13 PM   #2
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By attaching the volt meter to your battery, red to the positive and black to the negative, the output or volts with the engine running should be between 13.5 and 14.5 or so. This test pertains only to system output and other problems such as bad alternator diodes and battery drains must be checked in other ways.
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Old 01-14-2008, 02:15 PM   #3
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voltmeter will only allow you to read system voltage. about 14.3 vdc @ 2000 rpm depending on batt condition. will need ammeter to read system amperage coming from alt. check manual for full field testing.
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Old 01-14-2008, 03:33 PM   #4
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That meter will tell you just about everything you nee to know.
As stated above, test the voltage at the battery AND at the alternator.
They Should be virtually the same, but there might be a Small amount of voltage difference between the two, less than .2v
Set the meter to DC Volts, ground the black lead and put the red one to the the stud on the back of the alternator. With RPMs above idle you should read 14.xx volts. Same test at the battery, same reading.
Engine off, key off, same tests should get 12.xx.

Are you having battery problems? If so let me know and I'll walk you thru troubleshooting.
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