I purchased a Schumacher 1200A battery charger a few months ago and just last night tried to charge my 2007 Infiniti G35 battery. The vehicle gets limited use and when I went to start a week ago the engine turned over slowly, i.e. I though I would top off the charge. The charger indcated a 30% charge and the yellow LED was blinking indicating another issue. I allowed the charger to run set at a standard battery, 8amp charge and after a few hours the charger indicated a "bad battery". \r\nI disconnected the charger got into the car and it started immediately. Did I do something wrong perhaps the chassie connection was not as good as should have been; or is there something wrong with the unit. BTW the connection light was was on as per the instruction manual
Electrical Supplies - Schumacher - & Fast Charge Starter Charger
Answers & Comments
I don't think you did anything wrong. I think your battery is tired and can't take a charge deep enough as it used to. As batteries get older and after repeated discharge and recharge during normal operation, they start losing their ability to hold charge as deep as when new. This is gradual and after a couple of years they drop to 50% and less. I think your attempt was "gallant" and you did everything correct, but it sounds that battery has flatlined on you and "Doc, the patient is gone"