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    Battery draining ... could it be the alternator?

    Greeting everyone ... I'm new to forum and is hoping someone will be able to offer some suggestions and guidance to a problem I'm troubleshooting.

    The problem came about about about a month ago when I drove my 99 C3 and the entire dash light started dimming. The lights for the Tiptronic started flashing between the Manual and Automatic constantly. The gauges pretty much shutted down. Luckily I was just leaving the house and quickly drove back into the garage. It seems the battery had died.

    I figured I'll recharge the battery which should fix the problem. I recharged it and everything looked fine. When I turn on the ignition, the voltmeter displayed 12 volts. The voltage on the cluster dropped slightly, and the ABS and Battery light were illuminated on the cluster. I figured if I drove the car, the alternator will charge up the battery. Well, it did not ... as I drove for a couple of minutes, the voltage dropped further and eventually when it dropped to 10 volts, I turned around and went straight home.

    This problem started when I left the car in the garage for a week and the battery died. I jumped start the vehicle and drove and everything seems fine. I later left the car idle for another 3 days and faced with the same problem ... dead battery

    I replaced the battery with Interstate battery last week. When I started the car, the ABS and Battery light still illuminates and the voltage hovers below 12 volts. When I drove around for a while, the voltage on the cluster shot up just below 14 volts and the ABS and Battery light went away. I drove the car the following day and everything was fine until I parked the car for a couple of hours while I did a little shopping. When I returned and started the car, to my dismay, the ABS and Battery light is back on and the voltage hovers below 12 volts again.

    The battery was tested and confirmed in excellent condition. I am how speculating if the problem could be a problem with the alternator. I did a some research on another forum and there have been mentioned of regulator on the alternator that may be the problem. I am unsure what the regulator does. Has anyone experience a similar problem with mine?

    I would appreciate any suggestions and guidance.



    Re: Battery draining ... could it be the alternator?

    my apologies .. typo error ... meant to say 99 C2, not 3

    Re: Battery draining ... could it be the alternato

    Problems with the alternator and battery drain normally mean the diodes are shot allowing the battery to discharge. But you need to test for this.

    What you want to do is hook up an ameter (in series, remember) with the battery and start pulling fuses until the voltage drops to the normal level. What the normal level is i don't know for the 996 but it shouldn't be too difficult to distinguish a voltage drop from the present level.

    The circuit that shows the drain should then be investigated to find your problem. If you are at any point uncertain, you should consult an auto-electrician instead.




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