Hello I'm new to this forum. I am working on my grandma's 91 1991 Cadillac eldorado Seville 4.9L, the car has been sitting out side for about 4-5 months. I went to start it the other day and it acted like it wanted to turn over but never did. We charged the battery and even tried a new battery and just put in a new starter today, the engine still will not start. When we were trying to get it started the info center said wait 3 Min's, so we did and still wont start. All the lights light up on the dash and as soon as you turn the key to the start position all of them go off and you don't hear anything, like the solenoid on the starter. I was reading some where about some kind of security system and the key not letting the engine start? Could this be the issue? If so can some one explain to me what needs to be done to get the car to start. Thanks

 

Theft deterrent problem, VATS module is not reading key. Most likely will need new ignition cylinder and key.

 

i just had the same problem with my seville. all i did to fix it was, take a multimeter and test the black box on your key, called pass key, then go to radio shack and get some resisters and put them together till` you get the exactly the same ohms then trace your two wires coming off your ignition down to the connectors under the dash loop the ohms wires you made into the positive and negitive ports then start your car

 

we also have a thread in the FAQ that explains that with pictures.


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