Battery problem

SON240sx Automotive
1

okay guys got a problem my battery light is on and wont turn off , the car keeps shakein up and down back and forth, like a rumble.

i tried a new battery same problem , ive got to answers the alternator and the grounding wires, someone told me if i turn it on let her run and take off the positive and negative terminals to the battery without the car turning off then its not the alternator , which i did and it didnt turn off.

shes also reving 500 when in drive about 800 in n or p

Someone please help its driven me crazy

2

Your low idle is probably the problem.

With the idle so low, the motor isn’t spinning the alternator fast enough.

Battery voltage is lower than where it should be, so the battery light comes on.

3

Does the battery light go off when you are driving or revving the engine??

4

yeah the battery light turns off when i start goin about 100, so how do i fix this ?