Hi Peter its not that the program changes but the CCU just go's faulty and thats funny because the last one I did was car sales and that had been on the front of the garage for 3 or 4 months, you can program the locking system by switching that LSB to 1 or 0 this switches on and off the selective unlocking, you will find that when you switch the locking system will work ok in standard mode LSB set to 1, but when in selective mode LSB set to 0 it will only unlock the Drivers door, the CCU will have to be replaced if you wont to get the selective locking working again,