BMW Thermostat

Oct. 18, 2019

This bulletin applies to 2016 BMW 228i xDrive vehicles. A fault code 1D2008 may be stored in the DME and the service engine soon light is on.

The fault code refers to the map thermostat jammed open. There may also be a complaint of low heat output with lower outside temperatures.

During engine warmup, the engine coolant does not reach operating temperature within the DME’s allowable time frame. This is caused by either a faulty thermostat inside the transmission oil heat exchanger or a faulty engine characteristic map thermostat.