What's the BMW fault code 1d2404?

The BMW Fault Code for the diagnostic trouble code 1D2404 is a "Map Thermostat Error". If You get this code, You might have also noticed that the engine temperature has exceeded the quarter mark and the radiator's been kicking in at the maximum RPM, to the point that You feel vibration on the steering wheel! The most likely cause of this error is that the cable for the thermostat, which sits under the radiator, has become disconnected. You can't normally see this from above, but if You jack up Your vehicle, remove the under-carriage cover, and look underneath the radiator, You can verify whether it's properly plugged in, and if not, remedy.