Cadillac Repair: cadillac seville wont start, negative battery cable, sears store

Question
After driving the car for a period of three weeks,then not driving it for a week,it wouldn't start. I thought it was a slow drain on the battery because of the installation of a new radio,so i disconnected the radio. There was still a slow drain on the battery so i replaced the altinator, there is still a slow drain on the battery and the car still wont start.

Answer
Hi Charles, Since you don't say what year the seville is this is what I would recommend you do. You will need to get an ampmeter that is capable of reading as low as .07 amps or 7 milliamps and up to 20 amps. A digital meter that is auto rangeing or a meter that has a clamp over probe and auto ranging would be the best. If unsure go to Radio Shack or the Sears store and ask. Then disconnect the negative battery cable and install the neg lead to the battery and the pos lead to the neg cable. Useing a 3/8" nut and bolt will work good to screw into the battery and put on the cable bolt. Now turn the key on to light the dash BUT DO NOT START THE ENGINE. Then turn the key to off and take the key out of the ignition and close the door. After 30 minuits the computors should have powered down and the ampmeter should read less than .25 amps or 25 milliamps. If it reads higher then that means there is a draw somewhere that is useing power out of the battery. Look inside the car to make sure that a light isn't staying on or in the glove box or trunk. If nothing is obvious then remove the fuse for the interrior lights, leave the door open and you might have to wait up to 30 minuits for all the computors to power down again. After that time if the reading is still high then start removeing fuses one at a time and if the reading doesn't drop right away then reinstall that fuse and go to the next one until you remove the one that causes the reading to drop to less than 25 milliamps. Depending on the year of your Seville you could have fuses under the hood, under the dash, in the trunk or under the rear seat. You could have a computor or module that isn't powering down and until you unplug it the draw will still be there. A height sensor could cause a drain as would an alternator. This is a search like a scavenger hunt but until you can find the fuse that is causing the draw and then unplug things on that circuit until the draw goes away I would caution you not to replace any more parts. A shop manual with good wireing diagrams would be vey useful. If you are unsure how to do this then take your car to an ASE certified shop and have then look at it. This might be an expensive repair and I definately wouldn't take it to a shop that advertises that "we do that"  Good luck. Bill