can't tell if my alt bad by voltmeter readings?
#1
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can't tell if my alt bad by voltmeter readings?
ok so my cars going through the common symptoms of bad alternator but it just started happening all at once. so i put the voltmeter from post+ to post- and got about 12v. from alt+ to alt frame, 10.6v. alt+ to bat+ .3v. and alt frame to bat- was like -70.8v?
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i also talked to the lady i bought the car from. she said there used to be a problem in the wiring around the driverside back fender well inside the car but they got it fixed. what should i be looking for?
#4
I think your alternator is just bad in general. The battery should ready ~12.7V just by itself, and around 14V when the car is running off the alternator. It doesn't seem like your battery is charging and your car is running off your battery, so it drops to 8V.
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as a general rule if you start the car, put the lights on, blower on full ,wipers on, you should still have over 12v also to check for shorts, with the car off take the + lead off the bat. and measure current between the + wire and the + terminal on the bat. If its over .01 amps start removing fuses till the current draw goes away then trace that circut. but it sounds like you have a bad atl. take it out and go to a parts store sometimes they have a bench tester.....good luck
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did what you said. was pulling .022amps. started pulling fuses, when i got to the hazzards one, i pulled it and it flat lined the gauge. i plugged it back in and heard my cd player make the (get power) noise and started pulling .009. could that be anything?
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