2E7C is a BSD data bus communication fault. On BMWs that use the BSD bus, the DME communicates with several “smart” components over that single line, and when communication on that line breaks down, the DME can store 2E7C. BMW-focused diagnostic sources repeatedly identify the BSD participants as the IBS (Intelligent Battery Sensor), alternator/voltage regulator, electric coolant pump, and oil level/condition sensor.
