I bumped a really old thread yesterday on this topic, but thought I would start my own since, well, I felt like it. :-)
To see my comments there, visit:
Battery Symbol Flashing ??
Anyway, yesterday my battery symbol was flashing while waiting in line to pick up the kids from school. It was hot. Darn hot. I consulted my owner's manual and it did not specifically mention a flashing battery symbol, just the battery symbol in general. So I came home, did a search, and found the thread above.
This afternoon, I decided to to some checking around.
Step One: Check battery voltage -- The car had been sitting in the garage since yesterday, and the voltage as measured at the battery was 12.33
Step Two: Check for loose battery cables -- Lo' and behold, the negative battery cable was loose. So I tightened it up good.
Step Three: Start car, select test number 9 from the secret menu and have a look.
At idle, upon startup - 13.2
V to 13.3
At 3K - 3.5 K RPM - 13.5
V to 13.7
V as I cruised around the neighborhood
At idle, upon returning to garage - 13.5
Now, based on what I'm seeing, I am thinking that my alternator is charging. But as I said in the previous post, electrics are like a foreign language to me. Does what I am seeing make sense?
I would like to think that the ultimate culprit was the loose negative battery cable. Logic tells me that the alternator would not be able to charge effectively with a loose cable in the system, so maybe that's what caused the lamp to flash.
I'd love to hear other folks' opinions.