In regards to the battery drain, have you gotten a battery/alt test? Battery could be bad or the alt could have a failing diode causing a drain....

haven't done it yet but I plan on taking the battery in this weekend to at least get it checked out. ill let you guys know what the results are.

I've replaced the BCM in my Monte with one from Ebay. I'm not sure it has all of the options my car originally had (Alarm system? tire pressure monitors? No fog lights either.), but it works other wise. I was able to program it for my key fobs.

However, your radio will go into lock mode. I had to replace the radio anyway, so I modified the radio by removing a chip which either removes or disables the security of the radio. Since my radio is retained only to program options (it's in the trunk) I'm not sure I need a reprogrammed BCM.

I've also heard that you can't reprogram a used BCM, you need to get a new one and get it programmed.

If the security light flashes it means the key resistance does not match the resistance value in memory. This will cause the no start situation. You can do a security relearn, but since you also mention your lights tweaking out and battery drain I would suspect a defective ignition switch.


You can determine what circuit has the parasitic drain by monitoring the amperage of the battery while unplugging fuses one by one until you see an increase in amperage at the battery. If that circuit happens to be for the ignition then I would definitely take a close look at the ignition switch.