I've noticed the last few months that the battery tends to go own very easily.
I charged and checked the battery, which consistently read low CCAs. I checked the charging system and it read okay. So I warrantied out the battery, which was fairly new. Now, 4 or 5 months later, I'm having the same problem. The battery in the car won't seem to charge up more than 650 to 700 CCAs. Anybody have any clues????

 

For this, a meter is a must.

Under charge (at idle) you need at least 13.8volt across the battery. 14.4volt is better.
Off charge, off load, less than 12.6volt is not good.

The charge control system is of the "chopper" or switch mode type controlled by a microprocessor. A meter will read some voltage on the rotor (smaller) connexion of the alternator, but it has a huge amount of ac. on it, so an old type moving coil meter is better for this. Somewhere in the region of 4 to 8volt might be expected.

For fault finding, blame the micro-controller last.
Your alternator drive belt should be at the usual tightness, only half turn possible with strong fingers.
If you have a spare battery, try it with the usual serious precautions; your original battery might have a shorted cell.

Leedsman.