When the battery in the GI or Motorola 4DTV receiver dies then the receiver will no longer function. The battery has a finite life. It is important to know the DOM for your receiver. This can be determined by analysis of the serial number. The date is embedded in the unit serial number for all DSR920 and DSR922 receivers.
The 7th digit is the year of manufacture. "4" would mean 2004. The 8th, 9th and 10 digits indicate the Julian day on which the unit was manufactured in that year. Julian days are the numerical day of the year and run from 1 through 365 (or 366 in leap years). If the number was 031, that would mean Jan 31. If the number was 053, that would mean Feb 22, and so on.