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alternator test / replace ???

2461 Views 12 Replies 10 Participants Last post by  djsprinklesnjo
how can I test mine at home first of all ?

if I need to replace what are the options ? Eventually I'll add a stereo system with an amp on 4 three way speakers, and maybe a small sub woofer and small amp on that.

I have an Optima red top battery how long should it stayed charged with the car sitting with the positive cable removed ?
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Go out and get a multimeter, like the one below at Harbor Freight tools. Check the battery with the car off. Should be between 12 to 13 volts. Then start the car, and test again. If it now reads more, like 14volts, then your alternator is charging the battery. If its the same, check to make sure the wiring is not at fault. To do that, put the positive lead of the multimeter to the positive side of the alternator. Put the black/ground wire of the multimeter to the block, or a ground somewhere on the car. If the alternator does not read any better than the battery, then its bad. If its reading higher, like 14 volts or so, then it could be the wires or voltage regulator. There are alot of videos on the internet that shows this.

Digital Multimeter - Save on this 7 Function Digital Multimeter
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