Changed out your ECM? Your Ignition or BCM? Vehicle won't start now? Here is what you need to do so that you can get back up and running again. All the computer components have to recognize one another before your vehicle will function. Follow these steps. Good Luck.

*Ensure that vehicle has a fully charged battery before attempting this procedure. Low battery will effect effectiveness of procedure.

Disconnect battery for 30 seconds then reconnect. This step is so that everything is refreshed. (personal step, but I recommend it)1. Crank engine: should attempt to start then stall. Release the key but do not turn off. 2. Security light should be either on or blinking. Should continue to do so for approximately 10 minutes.3. When security light goes out turn key to the OFF position for 30+ seconds4. Turn key to the ON position but do not crank. Security light will stay lit or blink for 10 more minutes5. When security light goes out turn key to the OFF position for 30+ seconds6. Turn key to the ON position but do not crank. Security light will stay lit or blink for 10 more minutes.7. When security light goes out turn the key off then attempt to start the engine. If the procedure worked the engine should start.

Good Luck!