Two problems related to alternator/generator/regulator have been reported for the 1998 Cadillac Deville. The most recently reported issues are listed below.
After repairs the previous day, alternator again fried. The dealership now blames after market battery. Supposed dead cell. This instance almost caused a wreck on the interstate. Stranded for 3 hours. New battery and alternator. Car was dead when towed to the dealership. After finally arriving at end destination, I had the battery the was supposed to be bad checked and it checked out ok.
The volts went to 11. 1 and then the car failed to run. Dealership said that the alternator was fried. Replaced alternator. All other electrical checked out ok.