Keeping a battery charged

[apariah]

Any suggestions on how to keep a battery charged. If I start the car every other day, everything seems to be fine but if I let it sit for more than two days with out starting it the battery is almost dead.

My concern is that in two weeks it will be my daily driver, and it will be driven at night a couple times a week to and from Dallas. Could the problem be I'm just not driving the car, allowing enough time for the alternator to charge the battery. When I picked up the battery and istalled it started right, so I don't really think its the battery. Everything I've read about the miata battery seems it imply that it takes a while for it the charge.

Any suggestions?

[trackdog]

Did you have this problem before you installed the other battery? If so you may have a short or some electronic device draining the battery. Have you added a big stero amp? You could have a weak cell in the battery that won't hold a charge for very long, but you can test this. I would also suggest driving over to Auto Zone and have them do an alternator check for you, it is free and they can test the battery as well.

My gut feeling is that you might have some component draining the battery. Check the voltage of the battery when you get home and with a full charge. Then check the voltage again in the morning and see if it has dropped any. Since you are not driving full time yet, check the voltage the next day as well. If you are seeing a drain then the question is where.

I would also experiment with a charged battery and do the same test except take one of the terminals off so there can not be any outside source drain and see if the battery voltage drops over time.

Process of elimination.

Gary

[POS Racing]

My '99 sits weeks on end in the protective bubble and always starts when its time for an autocross.

I agree with trackdog you must have something sucking the life out of that battery.

[cone-cerned]

My '94 also sits for up to two weeks, not in a protective bubble, and always starts first time. The previous owner had put in a new Westco battery just before I bought the car in July 2006.

Do you have a multimeter to check the voltage with?

[apariah]

I'm not a car audio guy, and I don't think amps and huge speakers mate well with a NA 1.6, so I don't plan to add anything other than my Ipod, and a FM modulator. I did notice a little hole in the dash that may have housed a led for a alarm, and it looks like power to the cigrette lighter was cut, plugged in a moduclator and noticed the power light did not come on.

The car did come with an after market head unit installed, I'll take a look at it, this weekend to see if it looks like it could be shorting out some where. After that I think I may just need to do the auto zone thing and look from my multi-meter.

Thanks

Did you have this problem before you installed the other battery? If so you may have a short or some electronic device draining the battery. Have you added a big stero amp? You could have a weak cell in the battery that won't hold a charge for very long, but you can test this. I would also suggest driving over to Auto Zone and have them do an alternator check for you, it is free and they can test the battery as well.

My gut feeling is that you might have some component draining the battery. Check the voltage of the battery when you get home and with a full charge. Then check the voltage again in the morning and see if it has dropped any. Since you are not driving full time yet, check the voltage the next day as well. If you are seeing a drain then the question is where.

I would also experiment with a charged battery and do the same test except take one of the terminals off so there can not be any outside source drain and see if the battery voltage drops over time.

Process of elimination.

Gary

[apariah]

BTW when I picked up the car, the owner had it on a charger, he said it would not hold a charge. I drove the car home from Kellar to The Colony, and it started up again after I put in it in the garage. I triend it again a few minutes later and it was dead.

Did you have this problem before you installed the other battery? If so you may have a short or some electronic device draining the battery. Have you added a big stero amp? You could have a weak cell in the battery that won't hold a charge for very long, but you can test this. I would also suggest driving over to Auto Zone and have them do an alternator check for you, it is free and they can test the battery as well.

My gut feeling is that you might have some component draining the battery. Check the voltage of the battery when you get home and with a full charge. Then check the voltage again in the morning and see if it has dropped any. Since you are not driving full time yet, check the voltage the next day as well. If you are seeing a drain then the question is where.

I would also experiment with a charged battery and do the same test except take one of the terminals off so there can not be any outside source drain and see if the battery voltage drops over time.

Process of elimination.

Gary

[cam76034]

I did notice a little hole in the dash that may have housed a led for a alarm, and it looks like power to the cigrette lighter was cut, plugged in a moduclator and noticed the power light did not come on.

Bingo! My BRG has also had a security system, everything is disconnected except for a little light in the dash. If it isn't driven for a few days, that tiny little light draws enough to pull the battery down.

[motorollow]

My old car alarm also drains the battery after a couple of days without driving.

[trickyrix]

Sounds like a weak/dying battery to me. My old Camry would do the same thing. I milked it for 3 months with the occasional jump start until it just wouldn't start one morning in the grocery store parking lot - in the rain, in February, etc.

+1 for the AutoZone alternator/battery test... and if you have a multi-meter, you should be able to check and see if there's a drain on the system.

[apariah]

How can I use the multi-meter to tell me if I have a drain in the system. If I see voltage drop at the battery after a few ours is that the indicator?

Sounds like a weak/dying battery to me. My old Camry would do the same thing. I milked it for 3 months with the occasional jump start until it just wouldn't start one morning in the grocery store parking lot - in the rain, in February, etc.

+1 for the AutoZone alternator/battery test... and if you have a multi-meter, you should be able to check and see if there's a drain on the system.

[channelmaniac]

BTW when I picked up the car, the owner had it on a charger, he said it would not hold a charge. I drove the car home from Kellar to The Colony, and it started up again after I put in it in the garage. I triend it again a few minutes later and it was dead.

Was it dead dead or did it try to start but was weak... Sounds to me like you might have a shorted or leaky diode in the alternator.

One thing to do is (with the car off & key out) to take a 12v bulb and connect it in series with the positive terminal on the battery and the positive cable. If the bulb lights (or instantly burns out like a fuse!) up you have a current draw. Pull fuses one by one until the light goes out.

Once you find the one that is the source of the power draw you can then start tracking it down to the culprit.

Start with the radio and dash light fuses first.

[trickyrix]

How can I use the multi-meter to tell me if I have a drain in the system. If I see voltage drop at the battery after a few ours is that the indicator?

I'm thinking (and I could be totally effing wrong) that you could pull a cable off the battery and measure the current between the battery and the removed cable. As long as it's not so high that it blows your meter (which it shouldn't be with a slow drain), you should at least be able to tell if something is pulling down your battery.

My thought is that every car made within the last 20 years will draw a little something from the system... but it's not enough to kill the battery in a couple of days (maybe give it a month or two, worst case?).

Anyhow, my best guess is that your car just needs a new battery...

[apariah]

On that side of things, I notice my door buzzer was making weird sounds . I took a look at the wires going to the buzzer, and noticed one of them had a not so good tape job on a bare part of the wire. I couldn't figure out what the plug went to other than the buzzer so I pulled it. The car started fine, I'm about to head back out side and try it again. What does the buzzer do other than tell you the door is open.

Was it dead dead or did it try to start but was weak... Sounds to me like you might have a shorted or leaky diode in the alternator.

One thing to do is (with the car off & key out) to take a 12v bulb and connect it in series with the positive terminal on the battery and the positive cable. If the bulb lights (or instantly burns out like a fuse!) up you have a current draw. Pull fuses one by one until the light goes out.

Once you find the one that is the source of the power draw you can then start tracking it down to the culprit.

Start with the radio and dash light fuses first.

[Darron65]

You might be on the right track. You definitely want to check circuits like that; I mean ones that are powered constantly, not just when the key is switched on.

[channelmaniac]

What does the buzzer do other than tell you the door is open.

That wire gets grounded when you open the car door. If it's shorted to ground not only will the buzzer sound but the interior lights will stay on.

RJ

[apariah]

I left the buzzer unplugged, and replaced the battery, everything seems to be good so far.