A no load voltage test will only tell if you have voltage. A worn battery might show good voltage, but not flow any current under load.
Kinda like having poor flow from a hose attached to a water tank. The water tank may be full(like measuring 1.5 volts on a 1.5 volt AA battery). But, the hose may be restricted or clogged(ie no current flow from the battery).
Quote:
Originally Posted by Bird  My wife thought the 2 AA batteries in her TV remote were weak, too, so I went and bought new batteries this morning and put new batteries in her TV remote and in the HVAC thermostat. But then I went and got my multimeter and found the old batteries from the TV remote showed 1.3 volts, but the ones from the thermostat showed 1.5 volts. They are Duracells with a date on them of Mar 2013, so I don't think those batteries were the problem, but I left the new ones in anyway. |