i get a "BATTERY NOT CHARGING " message. I got the alternator rebuilt from 140 to 240 amps and battery is only 3 years old. It is an interstate 800cca. I had it load tested and it is just fine. mine is a 98 deville de'elegance. I upgraded the big three wiring (0 gauge) positive and negative wiring before all this started happening. I had put in a 1800 watt kenwood mono amp and two 12 inch subs so I figured I had better put in big wires. Things were working fine until i noticed lights dimming and amp cutting out after about 3-4 months. Then i started getting the "BATT NOT CHARGING " message so I had local alt shop rebuild alternator. So now with a rebuilt alternator and fully charged tested good battery only 3 years old, I am still getting the message and battery drains and discharges. Any ideas what this could be? I tried researching this elsewhere but could not find any definite sensible answers so I'm hoping the cadillac brothers out there can shed some light on this. THANKS!!.