Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
hello... there is a check you can do to see if it is the security system causing your issue...
to do the check... make sure the key has been off for at least 30 seconds... turn the key to the on/run position, wait for at least 5-7 seconds, attempt to start the car and release the key, (leaving it in the on/run position) see if the security light flashes in the drivers info center or I/P.
IF it does flash... the issue is most likely a faulty passlock sensor and the ignition lock cylinder and sensor will need to be changed.