[redzetec]

Hi all
I am new to this forum and hope someone can help. My battery was turning the car over slowly. Eventually it gave up and I bought a new one. 3 days it lasted and it is flat again. I have checked all lights and dont see any left on!! can anyone help me please?[???] [???]

 

[ArcticMynx]

sounds like your alternators bad... check the voltage while roff and while running when running it should be between 13.5-14.7 volts

 

[jetrinka]

14.66 VDC is the magic number you want. Chances are its been fully discharged now and needs a charging. Hook up a charger to it for around an hour and a half and then start it. If it ran for three days then I doubt the alternator is bad. Its more likely you have some sort of parasitic drain on the battery that just saps it while it sits off.

 

[mikebontoft]

yeah just for the record, mine runs usually around 14.7 [thumb] definitely most likely a bad alternator.... if you have other means of transportation (or just get it changed by a shop) you could, if you know how, take the alternator out and take it to, I believe, Autozone? it's one of those places that does the check on that stuff to see if they're good or not. saw it on a commercial [hihi]

 

[redzetec]

Thanks for the replies, the car was running 4pm Friday but when I went to start it on Saturday afternoon the battery was completely flat, no ignition lights or anything. Surely an alternator would not drain the battery overnight.[???]

 

[jetrinka]

Nope. Do you have a multimeter? If so do this. Disconnect the negative battery cable. Attach the positive lead of the meter to the negative battery post and the negative lead to the negative cable. This will tell you how much drain there is on the battery when the car is off. Here is a good how-to on what to look for and how to do it.

http://www.wikihow.com/Find-a-Parasitic-Battery-Drain

 

[compspeed]

easy test to check alt. while the car is running dissconnect the battery, if the car dies there you go bad alt. A car can run for three days on a faulty alt, as long as your not running headlights, AC, and or heater. If you was running it on friday, when you parked it did you try to start it right after you shut it off? If not, the electronics that runs a car will and can drain your battery flat like that. Have been in your shape many times!!!

 

[gonzorelic]

jump it off and drive it to auto zone or oreilly auto parts and they will check it for free.