Yes, its not uncommon. Check first to see if the security light is on, on the dash. This will indicate a passlock problem in the ignition system.
Most likely your ignition switch is bad
Possible a bad computer chip on your car igition key or you may have to get a mechanic to reset the sequrity code for you. Try a different ignition key before you do anything else. The chip is that little black thing that's on the side of your key. I had a mechanic bypass my security in the ignition.
The Aurora has a VATS ignition and either the contacts in the ignition lock are bad, the wires from the lock to the computer are broken or the VATS chip in your key is dirty or the contacts in the ignition lock is dirty and not making connection with the chip in the key.
If you have a chip in your key the chip may have gone bad or your ignition is not reading it. the car thinks someone is trying to steal it & stops ignition process. try to get a new key made. you may have to get it from a dealer.
What exactly is going on with the car that is making you believe that the ignition module is bad to begin with? Does it not turn over, no power, are there any lights that come on the dashboard? What kind of key is used in this car? Does it have a "chip" in the key?
Possible bad ignition switch
the ignition switch is bad. you have to replace the ignition switch and you will have to have a new key made with it. i just replaced it in my 1992 seville. that will solve your problem.
Most likely is a bad ignition switch or lock cylinder.
bad shocks! ...... replace your shocksimmediately if possible .
It could be as simple as replacing the ignition key. Each key has a chip that comunicates directly with the car. If the chip goes bad, the car's starter will turn over, but the engine will not start. There is no after market key that will work. You must purchase them from a dealer. Costly little buggers, roughly around $150....... what kind of vehicle is this?
It could either be a bad ignition coil, a bad ignition rotor, a bad ignition cap, a bad ignition control module (if equipped), or a bad coil to cap wire.
Note: Cyls Compresion is perfect, sparks, spark plugs, ignition coil, all is fine You have an ignition coil at rear of plenum. trace wires back to it...it is bad! Replace it and you should be fine!