Dead battery after two weeks...normal?

[Lil bastard]

What you describe is not normal. If the battery is new as you state, then the charging system, parasaitic draw or shorts are suspect.

Pull the battery completely and charge it using a charger with no more than 1.5Amps - Yes, they make 10 or 15 Amp battery chargers, but these are for convenience and NOT battery health. Using more than 1.5 Amps can overcharge the battery and overheat it causing water to boil out of the electrolyte ruining it's balance. The water vapor will vent from the battery and you will damage the plates reducing the battery's ability to accept and hold a charge.

Once charged, take a DMM (Digital Multi-Meter) and check the voltage across the battery terminals (not connected to the car), this should read approx. 13.2 VDC (each of the 6 cells in the battery produce approx. 2.2VDC (X6 = 13.2VDC).

Now connect the battery to the car and start it. Again check the voltage across the terminals (cables connected). It should now read 13.5-14.5VDC This is the power supplied by your alternator. If voltage does not fall in this range, suspect one or more of the 3 pairs of diodes in the alternator are bad requiring replacement of at least the diode pac (if alternator has some miles on it, suggest replacing with a rebuilt unit). Also, remove front engine cover and check deflection of te drive belt - it should be tight with no more than .5" deflection.

Finally, turn off car, disconnect the negative terminal and connect the DMM between the cable and the battery negative terminal. Your reading s/b less than 50 milliamperes. If more than 50 milliamperes, check that all doors are shut, nothing is powered by the Cig Lighter, trunk and 'Frunk' are closed and not powering their lights. If all found OK, go to the fuse box and one-by-one, remove each fuse and check DMM to see if there is any effect. Replace the last fuse before pulling the next. If the DMM drops when a particular fuse is pulled, there is a short somewhere in that circuit which needs to be found to remove the excess draw on the battery.

Cheers!

[Ricochetron]

That's a lot of good info to check. Once I get the optima battery I will have things checked out.

To answer preious questions, The car is completely stock with 9k miles. When I had the car delivered to the house (too much snow when bought) we had to leave the car running in the trailer to assure it started when it made it to the house (15 minute trip). We alreaedy knew the factory battery was bad and a new battery was on order. When I got the new battery, I trickle charged it to full charge then installed it. I then started the car and ran it for appx 15 minutes. The car was put back in the garage and two weeks later it was at 4 volts. There had to be a major draw somewhere or the new interstate battery was a dud.

Since the original battery was bad and the car probably required several booster starts, do you think the alternator was damaged in the process of jump starting?

[70Sixter]

Could be alternator/regulator if it discharges while driving.

Interstate batteries are good quality and warranted. If it is defective you should get a new one be reimbursed.

I routinely plug my Box into the battery maintainer when I park. I never know when I'll drive it next. Certainly if not run for a even a week it should be on maintainer.

Batteries hate recharges from low state of charge and will last longer if kept charged.

[Ricochetron]

Ok, I just installed a new Optima 34R battery with adapter plate. Battery is full of charge. Before connecting the negative cable, I checked the parasitic amp draw and found a whopping 1.2 amps. The 07 987 is completely bone stock. I unplugged the front boot light to get an accurate reading, (doors closed, everything in the off position.)

Is this what I should expect? No wonder why my earlier new Interstate battery went down to 4 volts in two weeks, ruining the thing.

[vath2001]

Step 2: With the amp meter hooked up, start pulling fuses. Pull a fuse, check the meter and re-install the fuse if no change to the meter. That will narrow down the circuit.

[jcb986]

Disconnect the front and rear trunk lights and then check your amps. Guys have had the switch go bad and these little lights will run down your battery if left on.

[stephen wilson]

Did your air bag light come on after the battery died? I left the lights of my 06 on, now I have a fault showing. I presume I'll have to have the dealer reset it?
Thanks,
Steve