I turn on the heater but cannot get any heat. on 2004 BMW 330Ci

No heat is coming from the system. Tried all controls

Asked by for the 2004 BMW 330Ci
could be as simple as low coolant level. this system uses
an electrically controller heater valve which may have failed. or it may have a problem in the controller. after
trying the basics, you should find a good local BMW shop
that can diagnose this.
1 more answer
no heat is coming from the system.only cold air blowing when heater turned on.