Washing machine is not heating the water due to a fault with the heating element.
If you suspect that your Siemens washing machine is not heating the water, either because the appliance doesn't feel warm during the wash cycle or because the clothes are not being cleaned properly, this may be due to a fault with the heating element, which is normally confirmed by the displaying of an error code. This is not a fault that you can repair yourself and will require a repair by a trained and qualified service engineer.
If you have followed the information above but you're still having problems with your Siemens washing machine, then you might want to have it checked out by a Siemens professional.