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Topic: something is draining my battery (Read 2339 times) previous topic - next topic

something is draining my battery

ive replaced my battery twice cuz something is draining it. im not leaving anything on so i dunno what it is. the alternator has been replaced so it should be charging my battery but it isnt. its a little unnerving driving home at night with dim headlights and no turn signals...any ideas?

Re: something is draining my battery

Reply #1 –
You are right! Your alternator is not charging.
Are you a do it yourself trouble shooter?
Some details on your car please, year, engine, is every thing stock?

Re: something is draining my battery

Reply #2 –
It sounds like the alternator is bad. Do you have reason to believe it is eating alternators? When you replaced it, did it work for awhile before it failed? How long? Was it DOA?
Places that sell alternators.Autozone,NAPA, PepBoys etc, also test them. Have it tested.
Handy tools to have are a volt meter and a battery charger.
A charged battery should be 12.5 volts with the car off. It should be 14 to 14.5 volts with the engine running if the alternator is charging.

Re: something is draining my battery

Reply #3 –
I know my old '85 302 did that for awhile until I figured out that I needed to replace the voltage regulator.  What is your car btw, cause I don't think my 87 has a regulator.  Somebody confirm or correct my hypothesis if necessary.
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

Re: something is draining my battery

Reply #4 –
well jump your car let it run and remove the postivie batter terminal if the car dies its your alternator.

Re: something is draining my battery

Reply #5 –
That is not good for the electrical system. If you have a voltmeter check the voltage. Should be about 12v when off and about 14.5v when running. Also shouldn't this be in electrical tech not audio?

Re: something is draining my battery

Reply #6 –
Quote from: --Cool-Thunderbird--
well jump your car let it run and remove the postivie batter terminal if the car dies its your alternator.


Not totally true....
If the car dies it may be that you just toast your EEC by doing this...
If you unplug/plug your battery while engine running, you remove the load of the system and the voltage peak for a sec risking  : Electronic failure (EEC, Amp, Head unit or anything else electronic, even the alternator itself)...

Or even worst, an explosion if your alternator was charging correctly...
Battery charging = Hydrogen
Hydrogen+Spark=Disaster

As lowcat said, use a voltmeter.... you should see at least 14v when engine running and 12.5 when engine off. If your battery cant hold 12.5v when disconnected, your battery IS the problem....