Dead Battery Gremlins

[shannonferguson2000]

My 2+2 must be sensing the tt swap soon to come. The past two days when i go to crank before work my battery is dead.(no lights on , no brake lights stuck )This just started out of nowhere. Being a new z owner this is something i haven't ever experienced, any ideas as to what my issue could be?

[audtatious]

Battery or alternator or power/ground connections. With the car cranked, if the alternator is trying to charge 13.8v+ at the battery then it's either the battery or connections that are bad.

[vitaminZ]

You can unplug your battery while the cars running...if the car stays running = alternator is pulling its load..but if the car dies = alternator isn't pushing enough juice.

It could be that the cells in your battery are toasted..( the alternator is TRYING To charge it, but its not being absorbed) if it has caps on top you could try filling it up with water to TRY to revive it, if all fails.

And if all that ^ passes you could just have a bad ground/connection somewhere sucking the juice from the battery while the cars off.

Andrew

[audtatious]

May work with a Z32 but with newer cars you don't want to disconnect the battery while running as it can create a spike via the alternator and cause damage.

[Zwicked]

Just use a multimeter at the battery terminals to see if you are getting a little over 14 volts when it's running to see if the alternator is functioning. A bad alternator can also draw power if the car is shut off. Also have your battery tested, maybe it just needs to be replaced.

[es.biggs]

Just use a multimeter at the battery terminals to see if you are getting a little over 14 volts when it's running to see if the alternator is functioning. A bad alternator can also draw power if the car is shut off. Also have your battery tested, maybe it just needs to be replaced.

Agreed. You can get a cheap multimeter from walmart for like <$20 but if you plan on using it more than every 6 months you might want to get something of better quality. When the car is off, the battery should be around 12.8 Volts and over 14 Volts when running. Like Zwicked said, you should go get your battery tested to rule that out...any Firestone or even Jiffy Lube (eek!) should have a tester and they probably won't charge you for the test.

If the battery and alternator are fine, it might be a parasitic draw then you have to use the amperage setting on your multimeter to check how much current is being drawn from your battery. Basically, you gotta start pulling fuses until the amperage reading goes down. FUN STUFF!

[shannonferguson2000]

thank you ,i will try all this stuff, can you feed a z32 after midnight?

[shannonferguson2000]

well i tested every fuse and most of the grounds, it turned out that the alternator itself was pulling 12.53 volts with the car off, installed a heavy duty switch and solved the problem, at least until i pull the motor for my swap

[Vanessalalinda]

thank you ,i will try all this stuff, can you feed a z32 after midnight?

[Zwicked]

Sometimes when an alternator's diodes go bad, it can draw power when not running. I would change out the alternator as it will quit charging soon.

[es.biggs]

Just use a multimeter at the battery terminals to see if you are getting a little over 14 volts when it's running to see if the alternator is functioning. A bad alternator can also draw power if the car is shut off. Also have your battery tested, maybe it just needs to be replaced.

You called that one!