What can drain the battery in my 09impala overnight
4 Answers
Most common is a bad alternator, it may check good but if the diodes are bad it can pull out power as well as make it. Computer controlled charging systems make it difficult for most parts stores cause they can’t check it right, so find a good independent shop that knows how to check the entire system. Won’t be the first time a computer has caused a battery drain problem.
beatupchevy answered about a year ago
You have a serious power drain , I guess the good part is being so bad it could be easier to find
What you have is a parasitic drain; an electrical short in the system that's like keeping a switch turned on. Cars today are filled with all sorts of electronic devices that tend to fail, or something in the wiring fails. And these things are time consuming to diagnose. In the fifteen years of your cars existence, you've approached the time when some parts virtually always go bad. So with the car turned off, go to your fuses one-by-one and check current flow. When you find current, that's something alive. It might be normal, like the security system or that signal that's always seeking a key fob. But what you're looking for is a system that shouldn't be on. Then follow it to find the culprit and fix it..... And this will give you the opportunity to buy a really nice multi-meter.
