Battery died Friday (it was going on its 3rd summer in Phoenix, I can believe it wanted to die; I, too, want to die in this heat). After a jump, I had it replaced about a mile from home. $180 later I went directly home to drink. Went briefly to the store Saturday, maybe 1.5 miles round trip?

Came out yesterday to start the car and it was deader than dead. (Aside: unlocking the car with the key in door instead of remote will cause the alarm to blare once the jumper cables are in place. Also, it scared the hell outta me.)

Took it to O'Reilly as they were the only place open, and they said the alternator was outputting at 12.something. Took it to mechanic today who said the alternator is outputting (is that the correct tense of verb? sigh) at 14.75 and apparently they ran a diagnostics, load testing, and checked for a power drain, and found nada. He did say I may have left a door ajar (this may have irked me more than it should have as he was just being helpful, but yes, as most of us know, it yell-beeps at you if you use the fob to try and lock the doors and one is not closed all the way).

I know he said they looked for a drain, but is there something that is a known culprit for this behavior? Or could it really just be as simple as "battery didn't charge all the way?" (Nothing with this car as been simple, but hey, I'd take a first...)


Thank you

 

The batteries that you buy at a store are usually only partially charged. This could also be the reason the "mechanic" was only seeing 12 volts, and wanted to sell you an alternator, as well as the other known ploy of squirting oil on your shocks and struts, so you think you need to replace them.

If I was you, I would put it on a GOOD trickle charger directly on the battery, for the night. Then disconnect the negative battery cable, and put a GOOD test light between the negative battery post, and the negative cable. You should see a dim glow in the test light, because of all the control unit and radio memories. If the light is bright, it means you have a significant draw. At that point, I would remove one fuse at a time, to see when the bright light gets dim. That would be the circuit that the problem is located. Then it is pretty much up to you to locate a short, or some honkin stereo amp, that was just installed, and was not hooked up to a relay. You would be AMAZED at how much one of them draws. Anyway, that is pretty much how a professional mechanic does it. Your disadvantage might be knowing how to read a wiring diagram.....Good Luck.....Mike

 

I'm not sure it was so much the desire to sell me an alternator as it was he had no damn idea (this was at O'Reilly's, since as I mentioned, they were the ONLY place open that day).

Mechanic ended up saying exactly what you did re: battery probably wasn't fully charged. (O'Reilly's didn't like much; said the mechanic was a "moron" who probably didn't check to make sure the alternator wasn't intermittently putting out low voltage, because "every single battery" at the store is "always fully charged off the shelf." He was slightly salty.)

Thank you so much for the helpful info; I'll be putting it to work now that I'm back at work where the fun tools are.