intermittent charging problem
06-27-07, 01:03 AM
#1
intermittent charging problem
This problem seems to come and go. I tried everything in the Haynes manual, which proved to be about as useful as a Microsoft troubleshooting screen ("Did you plug your computer in, hyuk?"). So, since everything listed seemed good and since my voltmeter showed 12V at the alternator, I pulled the alternator. It tested good at Kragen, so I put it back in and it worked again. Then after a couple days it failed again so this time I left it in and drove down to Kragen. Right before I got there my battery suddenly dropped to 10V. Kragen tested it and found out that it blew a cell. I got a new battery. Then they verified that the alternator still wasn't charging my battery (while in my car) and replaced it under warranty. The new alternator worked right away. Then a few days later I got the same problem again: voltage at both alternator and battery reads 12V. The voltage is a hair lower at the alternator.
Before the problem hit I noticed something else. Whenever I turned on the headlights or rear defroster or etc. the voltage dropped a little but didn't go back up. With all the electricals on I was down to 12.5-13V, no matter how high I revved. The Haynes manual says it should go back up. It says absolutely nothing about what to do if it doesn't, though. At idle the voltage was always 12V but it quickly hit 14V (if headlights/etc. off) at even 1500rpm (maybe lower).
After the charging system failed again I unplugged my voltage regulator just to see what would happen (the voltage should go way too high, I think). Nothing happened. The battery reads ~12V when the car is off, and only slightly lower when the car is running. Again, the alternator reads a hair under that. I don't know when or if it will start charging again.
Before the problem hit I noticed something else. Whenever I turned on the headlights or rear defroster or etc. the voltage dropped a little but didn't go back up. With all the electricals on I was down to 12.5-13V, no matter how high I revved. The Haynes manual says it should go back up. It says absolutely nothing about what to do if it doesn't, though. At idle the voltage was always 12V but it quickly hit 14V (if headlights/etc. off) at even 1500rpm (maybe lower).
After the charging system failed again I unplugged my voltage regulator just to see what would happen (the voltage should go way too high, I think). Nothing happened. The battery reads ~12V when the car is off, and only slightly lower when the car is running. Again, the alternator reads a hair under that. I don't know when or if it will start charging again.
06-27-07, 11:20 AM
#2
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Battery blowing a cell usuall indicates overcharging. Overcharging will boil the battery. If this is the case battery acid should have boiled out. This condition is usuall caused by a defective voltage regulator. If you send me your email address I can send you the factory alternator check out procedure. It file is too lage for this site. You will need a voltmeter and an ammeter with a 6o Amp range. aljdiamant@comcast.net
06-27-07, 02:31 PM
#3
Problem occured again with a new alternator.
System was at 12V (alternator not charging battery) when the battery blew a cell.
Gonna try asking again, shorter this time:
Alternator won't change battery. Already replaced both alternator and battery. Voltage on alternator reads 12V, same as battery. Problem seems to go away and and then come back after a couple days
System was at 12V (alternator not charging battery) when the battery blew a cell.
Gonna try asking again, shorter this time:
Alternator won't change battery. Already replaced both alternator and battery. Voltage on alternator reads 12V, same as battery. Problem seems to go away and and then come back after a couple days
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