Does your antena go up and down when the radio is turned on? If not check your antena motor, I just had the same problem with my Bonneville SSE, Charge the battery, go in the trunk, pull the carpet down on the pass side (where the antena is) and feel the motor or use an ohm's meter. If it is hot(carfule mine burned me) or has power to it, then there is your leak. Just unplug it or replace it. Hope this helps. Also if you have an SSE you may have the tire inflator in the trunk make sure it is off.
where is the airconditor drain hose on a 1999 Pontiac Bonneville
The radiator petcock drain on a 1999 Pontiac Bonneville is on the bottom of the radiator. Look for a small black plug that looks like the plug found on a thermos or cooler.
Look at the bottom or rear of the radiator
LOOK TOWARD THE REAR OF THE OIL PAN.
It is on the bottom of the engine block, just a normal hex bolt.
it reg=charges
drivers side bottom right of radiator remove shield and look for plug
under car folow ac lines into small tube protruding out near them
Right under the battery
take off serpentine belt unbolt powersteering pump and hoses and drain it. That's it.
drain is on the lower side of the radiator opposite of the fill neck. You will need to remove the splash shield from underneath the car to view the petcock. check out www.pontiacbonnevilleclub.com for more info.
Eveready batteries are a well known brand. The durability will depend on which battery that you buy, and the drain of the unit that the battery is in.