2001 Saturn L200 security light

A new bcm will have to be programmed with the correct mileage they come with zero miles on the new ones. Also they will load the correct calibration file options etc.

To put a new one in yes it will have to be programmed. I have never seen a bad BCm blow the horn on those cars but I have replaced tons of bad bcms on those cars. Is there ever any inop fuel gauge temp gauge power door lock it keyless entry if equipped? Also ever not able to get it out of gear?Random no starts? Those are common symptoms when those bcms fails. Also have you had it scanned for codes?If so what are the exact code numbers not code descriptions? If there isn't any codes in the BCm for pass lock sensor etc and the security light is coming on I would suspect a bad BCm. But a diyer scan tool won't read body codes on that car it will take a professional scan tool they don't sell at the auto parts store use at the auto parts store to read codes or free. But a diyer scan tool my show a communication failure code showing signs you may have a bad Bcm.

The fuel gauge is the number one thing I have seen effected by failing bcms.I have used bcms from 2000-2004 for testers to trouble shoot bad bcms when there failing from all the old ones I replaced.