2005 Focus ZX3 2.3 Auto 140,000 miles. no power at all but fires right up on jumpers and runs fine but dies if you turn on the headlights and completely dies once you shut it off. took it to autozone to have the battery and alternator tested he said the battery tested ok and when he went to run the alternator test the car died 80% through the test. the guy at autozone said its the alternator but i want to be sure because the more i think about it it seems like the alternator is whats keeping the car going. battery is 3 years old. Any help will be greatly appreciated thank you.
Sure sounds like an alternator to me! I had the similar symptoms on a Ford Econoline and the alternator was the culprit.
awesome thank you
Sounds like the alternator. But if it's been weak for a while , then the battery might be on its way out too.
thank you mountain man