Someone tried to steal my 2000 Chevy s10. I replaced the ignition cylinder which came with two keys. I tried to do the 30 minute relearn but the security light doesn't stay on long enough to do the procedure. Also how do I program keys to work? I just came across some info regarding the ignition cylinder with keys and the housing with security chip in it to buy as a bundle and that sounds like what I actually need. Please help! I am so frustrated! Thank you so much.

Just making sure that you did a proper relearn:

30 Minute Learn Procedure
1. Turn ON the ignition, with the engine OFF. 2. Attempt to start the engine, then release the key to ON, vehicle will not start.
3. Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF.
4. Turn OFF the ignition, and wait 5 seconds.
5. Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes, the vehicle is now ready to relearn the Passlock™ Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.
ImportantThe vehicle learns the Passlock™ Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
6. Start the engine, the vehicle has now learned the Passlock™ Sensor Data Code and/or password.

You might also check the 10A TBC fuse under the hood.
If the relearn procedure works, but you continue to have security immobilizer issues, you will probably need to replace the halo sensor. You can get a kit from GM.

Did you try relearn ?
30 Minute Learn Procedure
Tools Required
None
Turn ON the ignition, with the engine OFF.
Attempt to start the engine, then release the key to ON. The vehicle will not start.
Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF.
Turn OFF the ignition, and wait 5 seconds.
Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes. The vehicle is now ready to relearn the Passlock™ Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.
Important: The vehicle learns the Passlock™ Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
Start the engine. The vehicle has now learned the Passlock™ Sensor Data Code and/or password.
With a scan tool, clear any DTCs if needed. History DTCs will self clear after 100 ignition cycles.

2000 chevy cavalier ignition key reset

you will have to reprogram the ignition and key to the system immobilizer

You don't need to program key's with this anti-theft system , there is no chip inside . Did you get a correct lock cylinder. . On this system there is a pass lock sensor in side an the lock clinder has a magnet !
Passlock™ Sensor
The passlock™ sensor is inside the upper right side of the steering column. The passlock™ sensor contains 2 hall effect sensors. The tamper hall effect sensor is on the top. The security hall effect sensor is under the tamper hall effect sensor. Both of the hall effect sensors monitor the magnet of the lock cylinder through an opening. The tamper hall effect sensor is physically placed on top of the security hall effect sensor. This arrangement enables the tamper hall effect sensor to engage first if an intruder attempts to bypass the passlock™ sensor by placing a large magnet around that area of the steering column. There is a tamper resistor inside the passlock™ sensor in order to help prevent tamper to the system. Passlock™ equipped vehicles have a selection of 10 different security resistors ranging from 0.5K ohms up to 13.6K ohms. Installing one of the security resistors inside the passlock™ sensor will generate a unique passlock™ code. All 10 combinations of the passlock™ sensor have the same part number. However, you cannot simply replace the passlock™ sensor and expect the system to operate properly. Always start by performing the Diagnostic System Check first and following the instructions.
Body Control Module
The Body Control Module (BCM) contains the theft deterrent system logic. The BCM reads the passlock™ data from the passlock™ sensor. If the passlock™ data is correct, the BCM will pass theft. The BCM will then transmit the code password to the VCM/PCM.
During the tamper mode the vehicle may start. The vehicle will then stall. If the BCM receives the wrong passlock™ data, the VTD will immediately go into the tamper mode. The tamper mode will lock-out the vehicle fuel injectors for 10 minutes. The SECURITY indicator will flash while the VTD is in the tamper mode.
If the passlock™ sensor sends a correct password to the BCM when the ignition is in the ON position, the BCM will send a fuel enable signal to the VCM/PCM. The VCM/PCM will not disable the fuel due to any BCM message for the remainder of the ignition cycle.

You only need to do a relearn if one of these are replaced
Use this procedure after replacing:
• Passlock™ Sensor
• BCM
• VCM
• PCM

Did you replace any of these ?

30 Minute Re-Learn Procedure
Turn ON the ignition, with the engine OFF.
Attempt to start the engine, then release the key to ON (vehicle will not start).
Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF.
Turn OFF the ignition, and wait 5 seconds.
Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes ( the vehicle is now ready to relearn the Passlock™ Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK).
Important: The vehicle learns the Passlock™ Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
Start the engine (the vehicle has now learned the Passlock™ Sensor Data Code and/or password).
With a scan tool, clear any DTCs if desired (history DTCs will self clear after 100 ignition cycles).

if you replaced the ignition cylinder housing as well the passlock system will have to be relearned. Hook some sort of battery charger or stabilizer. attempt to start the vehicle and just release the key to the running position....check security/theft light on or flashing. after about 10 minutes the security/theft light should go off, turn key off but dont remove for 5 seconds, then attempt to start again. Do this 3 times for a total of roughly 30 minutes and it should start.

There is a problem with the theft system. This is the system that pervents the car from starting if the ignition lock cylinder is damaged when someone trys to steal the car.
You can try and do a relearn, it may let the car start after this relearn. The most common cause for this concern is the ignition lock cylinder, it has a computer sensor inside that goes bad, you have to replace the cylinder and program it.
To reprogram/relearn, put on the parking brake(this will keep the headlights from comming on and draining the battery), try to start the car, leave the key in the "on" position. The security light should no be flashing. Wait for tem mins, the light should turn off. At this time, turn the key off for 2 seconds and try to restart. At this point, the car may start, if not let the key stay in the "on" position again for tem mins untill the light turns off. Again turn the key off and try to start the car. It may take 3 times for the system to relearn, if you try 3 times and still no start, you will have to replace the ignition lock cylinder.

Your Passlock may need to relearn the ignition keys, if the ignition lock has gone bad like my in-laws Grand Am Gt, here is what i did so they will not get stranded any more. Buy a Passlock by pass module for around $70.00. You can order one from GMPASSLOCK.COM in the mean time try resetting the Passlock. Good luck

Ignition keys relearn takes about 30 min to do. 30-Minute Learn Procedure
1.) Turn ON the ignition, with the engine OFF.
2.) Attempt to start the engine, then release the key to ON; the vehicle will not start.
3.) Observe the SECURITY tell tale light. After approximately 10 minutes, the light will turn OFF.
4.) Turn OFF the ignition switch, and wait 5 seconds.
5.) Repeat steps 1 through 4 - two more times - for a total of 3 cycles of 10 minutes. 3x10 = 30 minutes.
The vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch turn from OFF to CRANK Important: Turn the Ignition Switch OFF. The vehicle learns the Passlock Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
6.) Start the engine. The vehicle has now learned the Passlock Sensor Data Code and/or password.
7.) With a scan tool, clear any DTCs if needed. History DTCs will self clear after 100 ignition cycles.

Without a scan tool you may have momentary starter interruptions while history clears itself.

If you just replaced the ignition switch then there are no additional procedures.The vehicle should start.If you replaced the ignition lock cylinder then you have the do a relearn.This is done by 1.attempt to start the vehicle.The vehicle will not start when key is released.Do not turn the key off after releasing it just leave it in the run position.The security light will come on for approximately 10 minutes then go off.Turn off the ignition and wait 5 seconds then repeat this two more times.For a total of 30 minutes.After the last time when you go to start it it will learn the pass code.Make sure you turn the ignition off after the last 10 minutes and wait 5 seconds before attempting to start the vehicle.The vehicle should now start and run.If not retry from the top. Hope this helps.Good luck.

Your ignition key may be excessively worn. The tumblers in the ignition lock cylinder read a worn key as someone trying to steal the vehicle. Have a new key made.

Someone may have tried to steal the car and damaged the lock's internal pins. Replace the entire lock with new.