Cadillac Repair: 95 caddy concours wont start and no power, cadillac deville concours, dash engine

Question
I went to start my car(1995 Cadillac deville concours 4.6 lt.) and nothing happened no lights on the dash turned on no power locks engine wont turn over nothing! went and had battery checked and autozone said battery is ok and fully charged came back home same thing no power,no lights on dash engine wont start do you have any ideas??P.s. checked again and battery makes bad smell and one cell smokes as soon as i plugged in positive cable to battery (this happens almost instantly when the wire touches the positive terminal) could this be alternator bad battery passkey system????

Answer
Hello,

One of the worst places one can go is to the discount parts stores. They sell parts, they are not capable of diagnosing anything.

The battery should not be smelling of acid. The first thing I would do is replace the battery. Then check the voltage at the battery with engine running. Voltage should be 14.2.
If that is good and you still have problems and you need to check for a parasitic draw.
Try the battery first.

Good luck,

Rob