While you wait for answers, we may have found some information which could help you.
Click here for Switch Button TumbleSwitch on button for Siemens WT2100 dryer stuck,want it to pop up?
Siemens WT2100 Tumble Dryer is just blowing cold?
siemens wt2100 dryer gets hot but does not seem to blow air, filter is clea?
Unlocking a Siemens Tumble Dryer showing the key symbol?
siemens tumble dryer not drying?
How can I fix my siemens fxl720 tumble dryer?