Charging System Check
shenning
01-09-2008, 12:24 PM
I have a '99 GP GT, 3.8L. I suspect that my alternator is bad, as the battery indicator is on. Also, some other indicators (ABS, TRAC Off, etc.) come on intermittently. Does anyone have a reasonably easy way to test the charging system to try and determine the location of the problem?
Thanks!
Thanks!
richtazz
01-09-2008, 01:32 PM
Welcome to AF!
I moved your post from the tips and maintenance section to the main forums for visibility.
A voltage test with a DMM will give you a starting point. With the car off, the battery should have between 12.6 and 13.2 volts, and with the car running, it should read 13.8-15.2 volts. You can also do a visual inspection of the battery and cables. Take the cables off the battery and check for corrosion, as well as for leaking or loose side-posts on the battery (a fairly common issue on side-post batteries).
Other than the battery indicator, another cause of electrical gremlins on these cars is the ignition switch/harness assembly. The contacts get weak and arc, causing many electrical gremlins (DIC issues, blower speed issues, interior lighting problems, etc...). I don't think this is your issue though, due to the battery light being on.
I moved your post from the tips and maintenance section to the main forums for visibility.
A voltage test with a DMM will give you a starting point. With the car off, the battery should have between 12.6 and 13.2 volts, and with the car running, it should read 13.8-15.2 volts. You can also do a visual inspection of the battery and cables. Take the cables off the battery and check for corrosion, as well as for leaking or loose side-posts on the battery (a fairly common issue on side-post batteries).
Other than the battery indicator, another cause of electrical gremlins on these cars is the ignition switch/harness assembly. The contacts get weak and arc, causing many electrical gremlins (DIC issues, blower speed issues, interior lighting problems, etc...). I don't think this is your issue though, due to the battery light being on.
shenning
01-09-2008, 03:48 PM
Thanks for the suggestions. I'll give it a try.
shenning
01-11-2008, 03:49 PM
Just wanted to post a follow up on my earlier message. It turns out that the alternator was bad. It's replaced now and running great. Thanks again for the suggestions.
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