DRL Module on 2001 Malibu

Does anyone know where the DRL module is on a 2001 Malibu. I suspect it is defective on mine. I will get a Service Vehicle Soon light ONLY when the headlamps or not on (Manually turned on during the day). so the DRLs are the only thing I can think of that would be causing this. The come onand off like they are supposed to so I suspect what ever tells the BCM that they are on is defective.