01 Impala B2960

I have a 01 Impala that orginally had a p1626 code in it well I put a Ignition cylinder in it. That code reset again not immediately but with in about 3 hrs of on and off driving. I put a BCM in it had to get GM to program it because of the 7 VIN digit. The code came back again, so I bypassed the ignition key with a resistor, and now the car has a B2960 in the BCM that keeps on resetting. And, the security light in the message box "in the dash" is coming on and staying on all the time after the car runs for a few mins.

B2960- Security system data wrong but valid

Is there anyone who has had this problem before after putting in resistor in the system to bypass the passlock and can help me ?

Any reply more than greatly appreciated.

Thank you,

Earl