Battery is good, but car won't stay charged
Just bought the car, mechanic thought the key stayed in the car and drained the battery in transport. Battery is a "gold" battery and was charged drove all day, then after leaving it sit for 5 hours, it's dead. What could be going on?
Thank you,
Amy
5 Answers
Simply having the key in it in "off" position will not drain battery You may have a drain for something such as an anti-theft device, all interiotior lights are off? Sometmes the switch gets bumped to 'on' . Have alternator checked also. Your car will drive a certian amount of time on battery, when the alternator goes bad but then it won't start. 5 hours of a, say, a dome/reading light should bit drain it that much
Thinking on this, how do you know for a fact the battery is good? Fing a volt meter, and put it on the battery, should show 11......12 volts. Get it running and do the same, should show 12 to 14 volts. BUT voltage and apmerage are apples and oranges, voltage my be fime but it's not putting out proper smpd. i.e. cranking power. If a non deep cycle isl allowd t go 100% drained it can ruin it
Disconnect the battery by removing the negative wire when you're done using the car. Draining all the power from a battery will kill it over time. It might not hold a charge any more. Read how many volts are in the battery when you disconnect it. Read it again in a few hours to see if it is less. A good battery should read somewhere between 12 and 13 volts. You disconnect the negative side so if your wrench hits anything metal, it won't draw a arc. ---- If your battery is good, hook it back up and attach the volt meter to the battery. Remove the larger. maxi fuses one at a time. They feed power to regular sized fuses. Pull the fuse and see if the volts increase. If the volts stay the same, replace the fuse and pull another one. If you see the volts rise a little when you pull the maxi fuse, you know that something in that circuit fed by that fuse is drawing the battery down.
If you have a 12 volt test light, with the ignition off, and everything else off, disconnect the negative battery clamp from the battery, place one end of the test light to the negative battery clamp and the other end to the battery post. If the tester light glows, something is drawing power from the battery.
