TrePound

hey my battery isnt charging back up. i have a good battery and a brand new alternator. but it still isnt charging it back up. my car ran fine before. but then the postive cable fell one the negative while it was connected. poeple said check fuses. but what fuse has to deal with alternator. like i said i have 5 different good batteries ive tried an also have a brand new alternator, but porblem still wont go away
my alternator is getting power from the battery cable thats connected to it. connectors are connected good.
heres a list of things ive tried
- change batteries
- change to a known working alternator
- check to see if power is going thru battery cable to the alternator
- check grounds
what else could i do or what else can i look at.
any help is greatly appreciated

MaxPower

Have you checked to see if there any voltage drops across your wires between the battery and alternator?

TrePound

well yea kinda. but i dont have dvm to test it out on. but i have a really nice 12 volt light that indicated that it was 12volts from the battery to the alternator. granted its not a dvm, but i know im close if not right at 12 volts. how would you hook a dvm to test for voltage drops.

MaxPower

Follow the flow of power with your DMM, to check the power side put the DMM positive lead on the alternator power and put the negative lead on the positive battery post. You shouldnt have more than .5v on your DMM. For the ground side put use the alternator case and the negative battery post.

I would first make sure you have at least 13v coming out of your alternator. Rev your car up a little then test the voltage, 13-14v is usually ideal.