[Mike1291]

Your car may also not charge at idle if your brush is only 1/3 down.Try going to a fast idle or just rev the engine slowly to see how much charge you are putting out at different RPM. The charge rate will cap out at a certain RPM, and for me that's somewhere around 2000. You want no more than 5 amps for short daytime drives, and around 2 amps if you drive for long distances.