CONTROL MODULES. Controller. front BCM. PartQualifier: front BCM. 315 MHz. An electronic control unit that monitors and controls various electronic systems in a vehicle's body, and communicates with other on-board computers via the car's vehicle bus. Ignition Immobilizer Module. Body Control Computer (BCC). Central Timer (CTM). Control switch. Controller support bracket. CTRL UNIT. Generic Electronic Control (GEM). Ignition Immobilizer.