alright here's the deal. my uncle's bmw525i battery died last night. his car is a 2001.
anyways the battery was replaced 2 years ago from sears. we will go get another battery and replace it.
but my question is what if the alt is bad? we can get a new battery but that will die fast also. so how can i check to see if the alt is good or not? if i stick a dmm and it reads 14volts+ does that mean the alt is good?
Good..... that is a easy way to blow the alt if it's still good. Some people don't understand that the battery has 2 functions, to supply power with the motor off, and to act as a buffer with it on. Without it the voltage regulator in the alt cannot handle the sudden changes in current draw and will be easily damaged.