I have a 1999 Gmc Jimmy and i think that i have accedently activated the Passlock security system and could not get the truck to start. well today i hooked the battery back up and it started but i still cant get the key out

1999 jimmys have a passlock system that is a theft deterrent and cant be "hot-wired" in the normal way. If the cylinder isn't rotated while beinging started correctly - the ecm will disable fuel to the injectors and it will not run

Without the proper testing equipment an knowledge ( factory service info. ) You have no idea what's up . an don't have a chance of fixing this . Checking for DTC'S - diagnostic trouble codes is always the first step . Take's a professional type scan tool to read these codes. Serial data info from module incharge to PCM/ECM ,enable or disable fuel and or starter operation . Sends coded messages Your best bet , take it to a qualified repair shop . That white component is the ignition switch .
The design of the passlock™ system is to prevent the vehicle operation if the proper ignition key is not used in order to start the vehicle. The mechanical key, in normal operation, will turn the passlock™ lock cylinder. The passlock™ sensor will relay the passlock™ data to the body control module (BCM). The BCM will determine the validity of the passlock™ data. The BCM will send a code password to the vehicle/powertrain control module (VCM/PCM). When the VCM/PCM receives the correct code the VCM/PCM allows the fuel injectors to operate normally. The passlock™ system requires the VCM/PCM and the BCM to communicate the various functions in order to operate. These functions transmit over the class 2 serial data line CKT 1807. For an explanation of the class 2 serial data operation refer to Data Link Communications Circuit Description in Wiring Systems

possible

1999 GMC Safari is equipped with a PassLock* system. It is designed to disable engine starting unless the ignition lock cylinder rotates correctly when the proper key is installed. The system is similar in concept to the PassKey* system. However, it eliminates the need for a key-mounted resistor pellet.
The components of the PassLock* system are as follows:
> The ignition lock cylinder
> The ignition switch
> The PassLock* sensor
> The PassLock* module
> The security indicator
> The Vehicle Control Module (VCM)

If any of the components (with the exception of the security indicator) is replaced, the PassLock* sytem must be reprogramed before engine start will be enabled.

When the system malfunctions, it is necessary to retrieve fault codes from the VCM to correctly determine which part of the system is causing the problem.

* "PassKey" and "PassLock" are registered trademarks of Genral Motors Corporation.

This car is equipped with Passlock antitheft security by GM. You dont have a chip, but there is a transponder in the key head. This system is known to fail. The fact that the security light is on proves the failure of the Passlock and why it wont run. The hard part is finding out which part of the passlock system has failed. Read this link for info and DO IT YOURSELF solutions to the problem.

http://vatspasslockpasskeysecurityhelp.yolasite.com/

If it is flashing it probably is killing the engine .

try disconnecting the battery should reset the system

check at battery for voltage with truck off,then check battery condition.it (the battery) could be weak.

try this, turn key on but do not try to start, walk away for 30 mins, turn key off for 1 min, then try to start