Advanced Auto battery test results




They said everything checked out fine. Which I suppose is good news but still perplexing. The tech said if you do not drive your car more than 30 minutes a week, then yes the battery dies. This happened to me in winter, but in September?


Starter and alternator test results

 

Get a DMM and check your battery. 12,31V is not a good charge. Charge your battery, measure the voltage with the Charger connected. Then take the Charger off and put the DMM on the battery to check the voltage. It should stabilize at 12,6-12,8V. Lower than that and i would change the battery due to sulfating cells. For voltage checks connect + and - of the dmm to + and - of the battery, set DMM to 20VDC. for current measurement put the dmm to Amps, remove the GND from the battery, + to the cable of the GND and - to the - battery pole. make sure you start in the highest amp mode as a low mode can harm your meter.

 

I don't drive the Lex every week and sometimes not for two weeks or more and Autozone said it is natural that battery will lose enough charge to prevent crank start. Further, driving only 30 minutes every week or two doesn't charge the battery enough back to close to full charge, especially in winter.
So my options are to use a trickle charger or 2) disconnect my battery till car is used (or use a battery disconnect switch lever installed on the battery or 3) the worst option, use a portable jumper every time it dies - which is what is currently happening

 

yeah i'm pretty sure if you don't drive you car a lot, the battery will die if connected.

 

Thoughts on this?

WirthCo (20138) Battery Disconnect for Top Terminal by WirthCo http://www.amazon.com/dp/B000CQBND0/ref=cm_sw_r_udp_awd_m1Xlub0JKX2AB

 

Usually a battery does hold its charge. As i said, measure the battery after charge and see if the voltage drops by itself. For me it sounds like a bad battery. Even if you don't drive a lot.

 

A battery disconnect switch does not fit on top of the battery as the hood will not close. I could try the screw kind but then the wife may not be able to do it on her own.

Anyway, the battery and altenator seem fine although I've been driving it every three days. I understand if the alternator were bad, well it would have the opposite effect and actually draw from the battery and the car would eventually stall if the battery was also dead.

So with the multimeter, something very interesting happens. Disconnected the negative terminal and put the meter in series. Set on 10A, the probes sparked a little when completing the circuit, and then showed 0.7 for about 5 seconds, then drops to .03. This is fairly consistent - I retest, add one probe, then the other, see a small spark, meter shows up to 0.7 and then drops to below .03.

I hope this is telling me that the draw is on average (and not parasitic), however why the initial spike?

Thanks!