Battery light stays on

[RickLew]

I have a 2007 Yaris with 88,000 miles. For the past two months my battery light in dash stays on if I let the car sit for a day or two. After driving it for 2 or 3 days, the light goes out again and stays out unless I let it sit again for a day or two. Anyone else dealing with this? Possible causes?
Thanks

[WeeYari]

There is a TSB that could be relevant to what you are experiencing.

I have same sort of issue periodically. Usually happens to me when there is an extreme amount of moisture in the air. Goes away after the atmosphere has dried out.

http://www.etimago.com/yaris/TSB/T-EL002-07(Charging%20System%20Warning%20Light%20ON%20).pd f

[supmet]

if I let the car sit for a day or two.

88,000 miles + letting your car sit a lot for days at a time = time for new battery

[WeeYari]

for some reason his link is blocked at work

is this with the check engine light that comes on? Mine comes on right before it rains or gets a lot of moisture in the air, then goes away a little bit later.

I didnt know there was at TSB for it

Not the check engine light. He would be referring to the red battery symbol. The TSB deals with an issue of corrosion in the voltage regulator on the alternator.

[RickLew]

Thanks WeeYari, I printed the TSB and will try.