Editing Toyota maintenance (section)

===Battery won't hold a charge, July, 2014===

Left some device on in the car for weeks and drained the battery down to the nubs.  After that, couldn't get it to hold a charge for more than a day.

Installed battery is a Les Schwab:

* Part number 35 XT
* Cold cranking amps: 640
* Cranking amps: 800

A battery with these specs isn't for sale anymore.  The battery that probably replaced this part has
590 to 900 cranking amps which carries a 7-year guarantee. http://lesschwab.com/batteries/browse-batteries/car-truck-suv

I can't remember when we bought this battery, but it was probably more than 7 years ago.


[[File:battery1.jpg]]
[[File:battery2.jpg]]

I was surprised to notice that I had access to fill the battery cells.  I asssumed it was all sealed up.  Looking in the cells, they had plenty of room for more water.  I added about 10 ounces to each of the two sets of three cells.  So 20 ounces in total.  And then put the 4 amp charger back on it for an hour.
Probably should have used distilled water.

* I observed that when the battery was low on fluid in the cells, I could attach the 4 amp battery charger and the charger guage would not go down.
* when the battery was filled with fluid, the charger started above 4 amps and went down to under 2 amps after 2 hours.
* after charging for two hours, the battery sounded healthy when starting the car.

* at rest, I measure the battery at 10.2 volts.  At this level, the car will not start.
* I attach the charger and set it to 4amps.  The voltage at the battery is now 12 volts.
* I start the car and disconnect the battery charger.  The voltage at the battery is now 14.6 volts.

I'd say that proves that the problem is not the alternator but the battery.  I'll drive to a parts store and pick one up tomorrow.

* after charging all night, the battery shows 14.06 volts
* four hours after charging, the battery shows 10 volts

Went to Les Schwabb and they tested the battery and found it wanting.  Replaced it with another battery with a 7-year warranty for $130.