Battery voltage in a 1995 Pontiac Bonneville?

The battery voltage in a 1995 Pontiac Bonneville, like most cars, should be around 12.6 volts when the engine is off and the battery is fully charged. It will be slightly higher immediately after charging. When the engine is running, the voltage should be between 13.5 and 14.5 volts. Anything significantly outside these ranges suggests a charging system problem.