The key is chiped , does it have a padlock an car symbol light on the instrument cluster when you turn the key on ? Do the headlamps work ? shine bright ? Do you have a volt meter ? Check battery voltage . Go to http://www.bbbind.com/free_tsb.html
free wiring diagrams . Enter vehicle info. year , make , model an engine size . Under system click on electrical distribution , under subsystem click on power distribution . Check power at the crank relay , plus you need to know what happens when you turn that key to start . Computers involved .Do you know about relays ?
Moving the ignition switch to the START position signals the body control module (BCM) through discrete inputs from the ignition transducer that engine crank has been requested. The BCM verifies that theft is not active and sends a serial data message to the engine control module (ECM)/powertrain control module (PCM) requesting engine start. The ECM/PCM receives a 12-volt signal from the park/neutral position (PNP) switch or clutch pedal start switch notifying that it is safe to start the engine. There is a splice on this circuit in the fuse block-underhood that supplies power for the starter relay coil. The starter relay coil control circuit is then grounded by the ECM/PCM closing the switch in the starter relay suppling 12 volts to the S-trminal of the starter. Ground is supplied through the engine block.
A scan tool of professional type would be a good tool to have to diagnose this .
The vehicle theft deterrent (VTD) system functions are provided by the theft deterrent module (TDM). When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the head of the key is energized by the exciter coils surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the TDM. The TDM then compares this value to a value stored in memory. This is the learned key code. If the value is correct, the TDM sends a random generated number to the transponder. This is called a challenge. Both the transponder and the TDM module perform a calculation on the challenge. If the calculations match, the TDM sends the start enable message via the serial data circuit to the engine control module (ECM). If either the transponders unique value or the calculation to the challenge is incorrect, the TDM will send the start disable message to the ECM via the serial data circuit. The components of the VTD system are as follows:
• Ignition key (Transponder)
• Ignition lock cylinder
• Security indicator
Is the light on . when trying to start the vehicle ?