no heat

Vehicle Application: 1997 BMW 740I 4.4L 2001 BMW 740I 4.4L Customer Concern: Vehicle does not have heat on high settings Tests/Procedures: 1. At the water valve assembly, mounted on the driver's side of the firewall, there should be battery voltage on the Red/Green/Yellow wire at all times. 2. The two control wires, Yellow/Brown and Yellow/Violet, receive ground signals from the climate control unit to shut the water valves off at low temperature settings. 3. If there is power and ground to the water valves, but there is still coolant flow through the heater core, the water valves are bad. Disconnecting the electrical connector to the water valves should give full heat. 4. If either power or ground is missing at the water valves, further diagnosis of the climate control unit and/or the switch unit will be necessary. Potential Causes: Water Valve Wiring Tech Tips: Water valve failures are relatively common on higher mileage cars. The diaphragm inside the valve weakens and cracks allowing water flow even with the valve electrically shut off.

I've got a 740 IL BMW with no heat all the controls are working blower is working what can I do