I have a 2004 Chevrolet Impala. Equipped with "Passlock" factory Theft Deterrent System. Anyway​ for the past couple weeks SOMETIMES I can try to start my car and it won't do anything. No crack or click or anything. Battery is good, changed the starter and checked fuses....etc. After researching via Google I've learned that year of the Impala is known for major issues with the factory Passlock system. Someone suggested using a passlock bypass module, is that possible? Or can this probably only be fixed by installing a NEW "KEY IGNITION?" PLEASE HELP!!!!!

 

Does the key have a small pellet in it? If so, you can either replace the key switch, or (and you will need to know which one it is 1-15). I had to replace mine due to being worn out. If you know the resistance, break the two small wires from the key switch to the body control module, install a 14 watt resistor. I've been told not to leave the resistor in all the time.