1996 Pontiac Grand Prix security system bypass?

Answer 1

Recent experience leads me to believe it can be done. I think one can use an (ohm) meter to find the resistance of the chip in the ignition key, and just jump the connection with the correct resistance. Get the resistors needed from Radio Shack and build a circuit that equals the needed ohms, and connect it to the wires instead of the orange 2-wire cable that comes from the VATS key tumbler. Your SECURITY light may come on and stay on, but at least the car will run. I have a 1996 Grand Prix I purchased used in 2006. A couple months ago I came out of a store to find my car wouldn't start, and a SECURITY light blinking while the key is on. The problem turned out to be a broken wire on the tumbler set. My mechanic installed a new tumbler set, I got a new key made at a GM dealer, and all was well. Thankfully I kept the old tumbler with it's broken wire, because tonight the car started blinking SECURITY and not starting again, and the old tumbler came in handy. (I suspect the wire broke on the new tumbler too, because the design is not durable...two small fragile-looking wires that move every time the key is turned are the weak link in the design.) Anyway, I had to plug the old tumbler back in, hold the broken wire together with one hand, and try to start the car with the other. Luckily, this worked. I now have a side-effect though. After the car was running, I didn't continue to hold the broken wires together, and the SECURITY light came on and stayed on throughout the 15 mile drive to my mechanic's garage. I expected to be unable to start the car again after turning it off, at least not without trying the wire trick again, but to my surprise the car now starts without the VATS key connection from the tumbler set plugged in at all! Trouble is, now I'm unsure whether and when I will have a problem again. My security system is not stopping the car from running even though I don't have the wires plugged in anymore. This is a good thing, until it decides to revert to it's normal function, which I'm afraid it will do at the worst possible time.