GMC Repair: Electricial Gremlin Nightmare, negative battery cable, 1997 chevy cavalier

Question
1997 Chevy Cavalier..one morning it will not start, jump start it, ran fine to work..after sits about 7 hours will not start again. I hold the key over sometimes it will catch, allways starts with a jump.Took it to dealer I bought it from used. He said it was a bad theft alarm module, charged me $130. to replace. Took car home next day car is dead again! I put a new battery in thinking it might be it, car started right up after I put in new battery but after sitting overnight it was dead again. Any idea? Also the dealer said he checked the alternator and it is ok.

Answer
Tony,
When the car sits and it won't start, check to see if you lights are nice and bright. If so using an volt meter see what the voltage is at the battery. It should be at the minimum  12 volts with everything off. If it is less that 12 volts you have a circuit drawing current. To check this, remove the negative battery cable, connect a test light to the negative battery terminal and to the  frame. If the light lights up there is a short somewhere. Then you need to start pulling fuses to see what circuit shuts the light off. Then that is where you have to trace wires in that circuit to see where the short is.  Also with the help of another person using the test light test the terminal on the starter solenoid ( the small terminal) and have someone turn the key to the start position. If the light lights up the starter is ok. If It does not light up. You need to replace your starter. Let me know if this helps you. Thanks for your question. jeff