Dave, if system voltage drops below a certain point for a certain amount of time, the SRS will disable. I can't recall the voltage, but anything below 11 or 12 volts would be about right. Check the alternator output with a volt meter. Cigar lighter socket is an OK source inside the car. Test with no load at idle, record reading, put a load on (headlights, fan, rear defrost, etc). Bring the RPM's up to about 1500. If you're not getting at least 13 volts, I'd suspect the voltage regulator. A new battery would mask the decrease in charging capacity initially. If you drive a lot at night, it won't for long, but daytime driving is less stressful on the electrical system. Good Luck.
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.